From 22481882192166554e2de99246d2522a72815ed4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=2E=20Fernando=20S=C3=A1nchez?= <balkian@gmail.com>
Date: Thu, 20 Feb 2020 11:28:55 +0100
Subject: [PATCH] Updated URL rdf and LOD

---
 lod/01_SPARQL_Introduction.ipynb    |  283 +++---
 lod/02_SPARQL_Custom_Endpoint.ipynb |   50 +-
 lod/03_SPARQL_Writers.ipynb         | 1417 +++++++++++++++++++++++++++
 lod/04_SPARQL_Advanced.ipynb        |  661 +++++++++++++
 lod/helpers.py                      |   12 +-
 lod/upload.sh                       |   53 +
 rdf/RDF.ipynb                       |  113 ++-
 7 files changed, 2406 insertions(+), 183 deletions(-)
 create mode 100644 lod/03_SPARQL_Writers.ipynb
 create mode 100644 lod/04_SPARQL_Advanced.ipynb
 create mode 100644 lod/upload.sh

diff --git a/lod/01_SPARQL_Introduction.ipynb b/lod/01_SPARQL_Introduction.ipynb
index 3f275e5..b375dbe 100755
--- a/lod/01_SPARQL_Introduction.ipynb
+++ b/lod/01_SPARQL_Introduction.ipynb
@@ -6,11 +6,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "7276f055a8c504d3c80098c62ed41a4f",
      "grade": false,
      "grade_id": "cell-0bfe38f97f6ab2d2",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -56,11 +57,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "99aecbad8f94966d92d72dc911d3ff99",
+     "cell_type": "markdown",
+     "checksum": "40ccd05ad0704781327031a84dfb9939",
      "grade": false,
      "grade_id": "cell-4f8492996e74bf20",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -69,7 +71,7 @@
     "\n",
     "* This notebook\n",
     "* External SPARQL editors (optional)\n",
-    "    * YASGUI-GSI http://yasgui.cluster.gsi.dit.upm.es\n",
+    "    * YASGUI-GSI http://yasgui.gsi.upm.es\n",
     "    * DBpedia virtuoso http://dbpedia.org/sparql\n",
     "\n",
     "Using the YASGUI-GSI editor has several advantages over other options.\n",
@@ -93,18 +95,19 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "99e3107f9987cdddae7866dded27f165",
+     "cell_type": "markdown",
+     "checksum": "81894e9d65e5dd9f3b6e1c5f66804bf6",
      "grade": false,
      "grade_id": "cell-70ac24910356c3cf",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
    "source": [
     "## Instructions\n",
     "\n",
-    "We will be using a semantic server, available at: http://fuseki.cluster.gsi.dit.upm.es/sitc.\n",
+    "We will be using a semantic server, available at: http://fuseki.gsi.upm.es/sitc.\n",
     "\n",
     "This server contains a dataset about [Beatles songs](http://www.snee.com/bobdc.blog/2017/11/sparql-queries-of-beatles-reco.html), which we will query with SPARQL.\n",
     "\n",
@@ -122,11 +125,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "1d332d3d11fd6b57f0ec0ac3c358c6cb",
      "grade": false,
      "grade_id": "cell-eb13908482825e42",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -144,11 +148,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "aca7c5538b8fc53e99c92e94e6818c83",
      "grade": false,
      "grade_id": "cell-b3f3d92fa2100c3d",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -163,11 +168,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "e896b6560e45d5c385a43aa85e3523c7",
      "grade": false,
      "grade_id": "cell-04410e75828c388d",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -193,11 +199,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "96ca90572d6b275fa515c6b976115257",
+     "cell_type": "markdown",
+     "checksum": "34710d3bb8e2cf826833a43adb7fb448",
      "grade": false,
      "grade_id": "cell-2a44c0da2c206d01",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -210,7 +217,7 @@
     "Some examples are:\n",
     "\n",
     "* DBpedia's virtuoso query editor https://dbpedia.org/sparql\n",
-    "* A javascript based client hosted at GSI: http://yasgui.cluster.gsi.dit.upm.es/\n",
+    "* A javascript based client hosted at GSI: http://yasgui.gsi.upm.es/\n",
     "\n",
     "[^1]: http://www.snee.com/bobdc.blog/2017/11/sparql-queries-of-beatles-reco.html"
    ]
@@ -221,11 +228,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "79c60bd3d4c13f380aae5778c5ce7245",
      "grade": false,
      "grade_id": "cell-d645128d3af18117",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -241,11 +249,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "f7428fe79cd33383dfd3b09a0d951b6e",
      "grade": false,
      "grade_id": "cell-8391a5322a9ad4a7",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -260,11 +269,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "f6b5da583694dd5cc9326c670830875d",
      "grade": false,
      "grade_id": "cell-4f56a152e4d70c02",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -313,17 +323,18 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "7a9dc62ab639143c9fc13593e50500d4",
+     "cell_type": "code",
+     "checksum": "3bc71f851a33fa401d18ea3ab02cf61f",
      "grade": false,
      "grade_id": "cell-8ce8c954513f17e7",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "SELECT ?entity ?type\n",
     "WHERE {\n",
@@ -338,11 +349,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "d6a79c2f5fd005a9e15a8f67dcfd4784",
      "grade": false,
      "grade_id": "cell-3d6d622c717c3950",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -375,17 +387,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "69e016b0224f410f03f6217ac30c03a8",
+     "cell_type": "code",
+     "checksum": "65be7168bedb4f6dc2f19e2138bab232",
      "grade": false,
      "grade_id": "cell-6e904d692b5facad",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "SELECT ?entity ?prop\n",
     "WHERE {\n",
@@ -401,12 +414,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "97bd5d5383bd94a72c7452bc33e4b0f9",
+     "cell_type": "code",
+     "checksum": "e78b57fa9baab578f5a4bd22dc499fca",
      "grade": true,
      "grade_id": "cell-3fc0d3c43dfd04a3",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -440,7 +454,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "SELECT ?type\n",
     "WHERE {\n",
@@ -465,7 +479,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "SELECT DISTINCT ?type\n",
     "WHERE {\n",
@@ -507,17 +521,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "47c4f68e342ffe59a3804de7b6a3909b",
+     "cell_type": "code",
+     "checksum": "35563ff455c7e8b1c91f61db97b2011b",
      "grade": false,
      "grade_id": "cell-e615f9a77c4bc9a5",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "SELECT DISTINCT ?property\n",
     "WHERE {\n",
@@ -532,12 +547,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "c9ffeba2d4ffc3e0b95f15a0ec6012c5",
+     "cell_type": "code",
+     "checksum": "7603c90d8c177e2e6678baa2f1b6af36",
      "grade": true,
      "grade_id": "cell-9168718938ab7347",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -569,7 +585,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
@@ -638,17 +654,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "8b0faf938efc1a64a70515da3c132605",
+     "cell_type": "code",
+     "checksum": "069811507dbac4b86dc5d3adc82ba4ec",
      "grade": false,
      "grade_id": "cell-0223a51f609edcf9",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
@@ -667,12 +684,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "e93d7336fd125d95996e60fd312a4e4d",
+     "cell_type": "code",
+     "checksum": "9833a3efa75c7e2784ef5d60aae2a13e",
      "grade": true,
      "grade_id": "cell-3c7943c6382c62f5",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -706,17 +724,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "271f2b194c2db4c558a46e8312b593e6",
+     "cell_type": "code",
+     "checksum": "b68a279085a1ed087f5e474a6602299e",
      "grade": false,
      "grade_id": "cell-8f43547dd788bb33",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
@@ -735,12 +754,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "9f1f7cec8ce4674971543728ada86674",
+     "cell_type": "code",
+     "checksum": "b4461d243cc058b1828769cc906d4947",
      "grade": true,
      "grade_id": "cell-e13a1c921af2f6eb",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -790,17 +810,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "9dcd9c6d51a61ac129cffa06e1463c66",
+     "cell_type": "code",
+     "checksum": "335403f01e484ce5563ff059e9764ff4",
      "grade": false,
      "grade_id": "cell-a0f0b9d9b05c9631",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
@@ -820,12 +841,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "a044b3fd6b8bd4e098bbe4d818cb4e9f",
+     "cell_type": "code",
+     "checksum": "45530eb91cbc5b3fddcc93d96f07e579",
      "grade": true,
      "grade_id": "cell-bc012ca9d7ad2867",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -867,17 +889,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "9da7a62b6237078f5eab7e593a8eb590",
+     "cell_type": "code",
+     "checksum": "8fb253675d2e8510e2c6780b960721e5",
      "grade": false,
      "grade_id": "cell-523b963fa4e288d0",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
@@ -898,12 +921,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "c8e3a929faf2afa72207c6921382654c",
+     "cell_type": "code",
+     "checksum": "f4474b302bc2f634b3b2ee6e1c7e7257",
      "grade": true,
      "grade_id": "cell-aa9a4e18d6fda225",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -945,17 +969,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "d8419711d2db43ad657e2658a1ea86c4",
+     "cell_type": "code",
+     "checksum": "c7b6620f5ba28b482197ab693cb7142a",
      "grade": false,
      "grade_id": "cell-e89d08031e30b299",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX m: <http://learningsparql.com/ns/musician/>\n",
@@ -975,12 +1000,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "29404e07edf639cdc0ce0d82e654ec31",
+     "cell_type": "code",
+     "checksum": "c90e1427d7e48d9ae8abab40ff92e3b0",
      "grade": true,
      "grade_id": "cell-903d2be00885e1d2",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1021,17 +1047,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "7a0a7206384e7e1d9eb4450dd9e9871f",
+     "cell_type": "code",
+     "checksum": "7556bacb20c1fbd059dec165c982908d",
      "grade": false,
      "grade_id": "cell-1429e4eb5400dbc7",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX m: <http://learningsparql.com/ns/musician/>\n",
@@ -1053,12 +1080,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "bd4dc379fea969d513be0ea97ee75922",
+     "cell_type": "code",
+     "checksum": "34a8432e8d4cea70994c8214ed0e5eb6",
      "grade": true,
      "grade_id": "cell-907aaf6001e27e50",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1094,7 +1122,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
@@ -1124,17 +1152,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "4a231b4d6874dad435512b988c17c39e",
+     "cell_type": "code",
+     "checksum": "2d0633303eedd0655e9b64bb00317dba",
      "grade": false,
      "grade_id": "cell-ee208c762d00da9c",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
@@ -1156,12 +1185,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "8118099bf14d9f0eb241c4d93ea6f0b9",
+     "cell_type": "code",
+     "checksum": "301aa479241fa02534ee047cf7577eee",
      "grade": true,
      "grade_id": "cell-ddeec32b8ac3d894",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1193,7 +1223,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX i: <http://learningsparql.com/ns/instrument/>\n",
@@ -1228,7 +1258,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX i: <http://learningsparql.com/ns/instrument/>\n",
@@ -1261,17 +1291,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "4b0a0854457c37640aad67f375ed3a17",
+     "cell_type": "code",
+     "checksum": "3bc508872193750d57d07efbf334c212",
      "grade": false,
      "grade_id": "cell-dcd68c45c1608a28",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX i: <http://learningsparql.com/ns/instrument/>\n",
@@ -1294,12 +1325,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "f7122b2284b5d59d59ce4a2925f0bb21",
+     "cell_type": "code",
+     "checksum": "69edef3121b8dfab385a00cd181c956f",
      "grade": true,
      "grade_id": "cell-1e706b9c1c1331bc",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1343,17 +1375,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "09621e7af911faf39a834e8281bc6d1f",
+     "cell_type": "code",
+     "checksum": "300df0a3cf9729dd4814b3153b2fedb4",
      "grade": false,
      "grade_id": "cell-0c7cc924a13d792a",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX i: <http://learningsparql.com/ns/instrument/>\n",
@@ -1379,12 +1412,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "cebff8ce42f3f36923e81e083a23d24c",
+     "cell_type": "code",
+     "checksum": "22d6fcdb72a8b2c5ab496cdbb5e2740a",
      "grade": true,
      "grade_id": "cell-2541abc93ab4d506",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1416,17 +1450,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "ea9797f3b2d001ea41d7fa7a5170d5fb",
+     "cell_type": "code",
+     "checksum": "e4e898c8a16b8aa5865dfde2f6e68ec6",
      "grade": false,
      "grade_id": "cell-d750b6d64c6aa0a7",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX  rdfs:  <http://www.w3.org/2000/01/rdf-schema#> \n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
@@ -1478,17 +1513,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "2d82df272d43f678d3b19bf0b41530c1",
+     "cell_type": "code",
+     "checksum": "fade6ab714376e0eabfa595dd6bd6a8b",
      "grade": false,
      "grade_id": "cell-2f5aa516f8191787",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX  rdfs:  <http://www.w3.org/2000/01/rdf-schema#> \n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
@@ -1513,12 +1549,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "bc83dd9577c9111b1f0ef5bd40c4ec08",
+     "cell_type": "code",
+     "checksum": "33e93ec2a3d1f9eb4b0310d4651b74c2",
      "grade": true,
      "grade_id": "cell-bcd0f7e26b6c11c2",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1567,17 +1604,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "a1e20e2be817a592683dea89eed0120e",
+     "cell_type": "code",
+     "checksum": "09262d81449c498c37e4b9d9b1dcdfed",
      "grade": false,
      "grade_id": "cell-d3a742bd87d9c793",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX  rdfs:  <http://www.w3.org/2000/01/rdf-schema#> \n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
@@ -1597,12 +1635,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "087630476d73bb415b065fafbd6024f0",
+     "cell_type": "code",
+     "checksum": "d583b30a1e00960df3a4411b6854c8c8",
      "grade": true,
      "grade_id": "cell-409402df0e801d09",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1648,17 +1687,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "1d2cb88412c89c35861a4f9fccea3bf2",
+     "cell_type": "code",
+     "checksum": "9ddd2d1f50f841b889bfd29b175d06da",
      "grade": false,
      "grade_id": "cell-9d1ec854eb530235",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "\n",
     "PREFIX  rdfs:  <http://www.w3.org/2000/01/rdf-schema#> \n",
     "\n",
@@ -1680,12 +1720,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
-     "checksum": "aa20aa4d11632ea5bd6004df3187d979",
+     "cell_type": "code",
+     "checksum": "0ea5496acd1c3edd9e188b351690a533",
      "grade": true,
      "grade_id": "cell-a79c688b4566dbe8",
      "locked": true,
-     "points": 0,
-     "schema_version": 1,
+     "points": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1738,17 +1779,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "508b7f8656e849838aa93cd38f1c6635",
+     "cell_type": "code",
+     "checksum": "d18e8b6e1d32aed395a533febb29fcb5",
      "grade": false,
      "grade_id": "cell-7ea1f5154cdd8324",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "PREFIX  rdfs:  <http://www.w3.org/2000/01/rdf-schema#> \n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX i: <http://learningsparql.com/ns/instrument/>\n",
@@ -1782,17 +1824,18 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
-     "checksum": "cff1f9c034393f8af055e1f930d5fe32",
+     "cell_type": "code",
+     "checksum": "f926fa3a3568d122454a12312859cda1",
      "grade": false,
      "grade_id": "cell-b6bee887a1b1fc60",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/sitc/\n",
+    "%%sparql http://fuseki.gsi.upm.es/sitc/\n",
     "PREFIX  rdfs:  <http://www.w3.org/2000/01/rdf-schema#> \n",
     "PREFIX s: <http://learningsparql.com/ns/schema/>\n",
     "PREFIX i: <http://learningsparql.com/ns/instrument/>\n",
@@ -1844,7 +1887,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.2"
+   "version": "3.8.1"
   }
  },
  "nbformat": 4,
diff --git a/lod/02_SPARQL_Custom_Endpoint.ipynb b/lod/02_SPARQL_Custom_Endpoint.ipynb
index 3e95636..37b2b89 100644
--- a/lod/02_SPARQL_Custom_Endpoint.ipynb
+++ b/lod/02_SPARQL_Custom_Endpoint.ipynb
@@ -6,11 +6,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "7276f055a8c504d3c80098c62ed41a4f",
      "grade": false,
      "grade_id": "cell-0bfe38f97f6ab2d2",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -31,11 +32,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "42642609861283bc33914d16750b7efa",
      "grade": false,
      "grade_id": "cell-0cd673883ee592d1",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -59,11 +61,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "a3ecb4b300a5ab82376a4a8cb01f7e6b",
      "grade": false,
      "grade_id": "cell-10264483046abcc4",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -80,11 +83,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "2fedf0d73fc90104d1ab72c3413dfc83",
      "grade": false,
      "grade_id": "cell-4f8492996e74bf20",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -100,11 +104,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "c5f8646518bd832a47d71f9d3218237a",
      "grade": false,
      "grade_id": "cell-eb13908482825e42",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -148,7 +153,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/hotels\n",
+    "%%sparql http://fuseki.gsi.upm.es/hotels\n",
     "    \n",
     "SELECT ?g (COUNT(?s) as ?count) WHERE {\n",
     "    GRAPH ?g {\n",
@@ -160,14 +165,12 @@
    ]
   },
   {
-   "cell_type": "code",
-   "execution_count": null,
+   "cell_type": "markdown",
    "metadata": {},
-   "outputs": [],
    "source": [
     "You should see many graphs, with different triple counts.\n",
     "\n",
-    "The biggest one should be http://fuseki.cluster.gsi.dit.upm.es/synthetic"
+    "The biggest one should be http://fuseki.gsi.upm.es/synthetic"
    ]
   },
   {
@@ -183,11 +186,11 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/hotels\n",
+    "%%sparql http://fuseki.gsi.upm.es/hotels\n",
     "    \n",
     "SELECT *\n",
     "WHERE {\n",
-    "    GRAPH <http://fuseki.cluster.gsi.dit.upm.es/synthetic>{\n",
+    "    GRAPH <http://fuseki.gsi.upm.es/synthetic>{\n",
     "    ?s ?p ?o .\n",
     "    }\n",
     "}\n",
@@ -233,13 +236,13 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/hotels\n",
+    "%%sparql http://fuseki.gsi.upm.es/hotels\n",
     "\n",
     "PREFIX schema: <http://schema.org/>\n",
     "    \n",
     "SELECT ?s ?o\n",
     "WHERE {\n",
-    "    GRAPH <http://fuseki.cluster.gsi.dit.upm.es/35c20a49f8c6581be1cf7bd56d12d131>{\n",
+    "    GRAPH <http://fuseki.gsi.upm.es/35c20a49f8c6581be1cf7bd56d12d131>{\n",
     "        ?s a ?o .\n",
     "    }\n",
     "\n",
@@ -264,11 +267,11 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/hotels\n",
+    "%%sparql http://fuseki.gsi.upm.es/hotels\n",
     "    \n",
     "SELECT *\n",
     "WHERE {\n",
-    "    GRAPH <http://fuseki.cluster.gsi.dit.upm.es/synthetic>{\n",
+    "    GRAPH <http://fuseki.gsi.upm.es/synthetic>{\n",
     "    ?s ?p ?o .\n",
     "    }\n",
     "}\n",
@@ -295,7 +298,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "%%sparql http://fuseki.cluster.gsi.dit.upm.es/hotels\n",
+    "%%sparql http://fuseki.gsi.upm.es/hotels\n",
     "\n",
     "PREFIX schema: <http://schema.org/>\n",
     "    \n",
@@ -308,7 +311,7 @@
     "        SELECT ?g\n",
     "        WHERE {\n",
     "           GRAPH ?g {}\n",
-    "           FILTER (str(?g) != 'http://fuseki.cluster.gsi.dit.upm.es/synthetic')\n",
+    "           FILTER (str(?g) != 'http://fuseki.gsi.upm.es/synthetic')\n",
     "        }\n",
     "    }\n",
     "\n",
@@ -339,12 +342,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "860c3977cd06736f1342d535944dbb63",
      "grade": true,
      "grade_id": "cell-9bd08e4f5842cb89",
      "locked": false,
      "points": 0,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -366,12 +370,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "1946a7ed4aba8d168bb3fad898c05651",
      "grade": true,
      "grade_id": "cell-9dc1c9033198bb18",
      "locked": false,
      "points": 0,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -393,12 +398,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "6714abc5226618b76dc4c1aaed6d1a49",
      "grade": true,
      "grade_id": "cell-6c18003ced54be23",
      "locked": false,
      "points": 0,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -449,7 +455,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.2"
+   "version": "3.8.1"
   }
  },
  "nbformat": 4,
diff --git a/lod/03_SPARQL_Writers.ipynb b/lod/03_SPARQL_Writers.ipynb
new file mode 100644
index 0000000..887108b
--- /dev/null
+++ b/lod/03_SPARQL_Writers.ipynb
@@ -0,0 +1,1417 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "7276f055a8c504d3c80098c62ed41a4f",
+     "grade": false,
+     "grade_id": "cell-0bfe38f97f6ab2d2",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "<header style=\"width:100%;position:relative\">\n",
+    "  <div style=\"width:80%;float:right;\">\n",
+    "    <h1>Course Notes for Learning Intelligent Systems</h1>\n",
+    "    <h3>Department of Telematic Engineering Systems</h3>\n",
+    "    <h5>Universidad Politécnica de Madrid</h5>\n",
+    "  </div>\n",
+    "        <img style=\"width:15%;\" src=\"../logo.jpg\" alt=\"UPM\" />\n",
+    "</header>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "2387a77db61721ecc375a8275111ecaf",
+     "grade": false,
+     "grade_id": "cell-0cd673883ee592d1",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "## Introduction to Linked Open Data\n",
+    "\n",
+    "In this lecture, we will apply the same SPARQL concepts as in previous notebooks.\n",
+    "This time, instead of using a database specifically built for the exercise, we will be using DBpedia.\n",
+    "DBpedia is a semantic version of Wikipedia.\n",
+    "\n",
+    "The language we will use to query DBpedia is SPARQL, a semantic query language inspired by SQL.\n",
+    "For convenience, the examples in the notebook are executable, and they are accompanied by some code to test the results.\n",
+    "If the tests pass, you probably got the answer right.\n",
+    "\n",
+    "However, you can also use any other method to write and send your queries.\n",
+    "You may find online query editors particularly useful.\n",
+    "In addition to running queries from your browser, they provide useful features such as syntax highlighting and autocompletion.\n",
+    "Some examples are:\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "bc0ca2e21254707344c60f895cb204b4",
+     "grade": false,
+     "grade_id": "cell-10264483046abcc4",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "## Objectives\n",
+    "\n",
+    "* Learning SPARQL and the Linked Data principles by defining queries to answer a set of problems of increasing difficulty\n",
+    "* Learning how to use integrated SPARQL editors and programming interfaces to SPARQL."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "2fedf0d73fc90104d1ab72c3413dfc83",
+     "grade": false,
+     "grade_id": "cell-4f8492996e74bf20",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "## Tools\n",
+    "\n",
+    "See [the SPARQL notebook](./01_SPARQL_Introduction.ipynb#Tools)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Instructions\n",
+    "\n",
+    "As in previous notebooks, the exercises can be done in the notebook, using the `%%sparql` magic, and the set of tests.\n",
+    "\n",
+    "\n",
+    "After every query, you will find some python code to test the results of the query.\n",
+    "**Make sure you've run the tests before moving to the next exercise**.\n",
+    "If the test gives you an error, you've probably done something wrong.\n",
+    "You **do not need to understand or modify the test code**.\n",
+    "\n",
+    "If you prefer to edit your queries in a different editor, here are some options:\n",
+    "\n",
+    "* DBpedia's virtuoso query editor https://dbpedia.org/sparql\n",
+    "* A javascript based client hosted at GSI: http://yasgui.gsi.upm.es/\n",
+    "\n",
+    "If you use an editor, make sure to copy it to the notebook and run the tests, once you are getting the expected results."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "c5f8646518bd832a47d71f9d3218237a",
+     "grade": false,
+     "grade_id": "cell-eb13908482825e42",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "Run this line to enable the `%%sparql` magic command."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from helpers import sparql, solution, show_photos"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "The `%%sparql` magic command will allow us to use SPARQL inside normal jupyter cells.\n",
+    "\n",
+    "For instance, the following code:\n",
+    "\n",
+    "```python\n",
+    "%%sparql\n",
+    "\n",
+    "<MY QUERY>\n",
+    "```    \n",
+    "\n",
+    "Is the same as `run_query('<MY QUERY>', endpoint='http://dbpedia.org/sparql')` plus some additional steps, such as saving the results in a nice table format so that they can be used later and storing the results in a variable (`solution()`), which we will use in our tests.\n",
+    "\n",
+    "You do not need to worry about it, and **you can always use one of the suggested online editors if you wish**."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Exercises"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### First Select"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Let's start with a simple query. We will get a list of cities and towns in Madrid.\n",
+    "If we take a look at the DBpedia ontology or the page of any town we already know, we discover that the property that links towns to their community is [`isPartOf`](http://dbpedia.org/ontology/isPartOf), and [the Community of Madrid is also a resource in DBpedia](http://dbpedia.org/resource/Community_of_Madrid)\n",
+    "\n",
+    "Since there are potentially many cities to get, we will limit our results to the first 10 results:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "SELECT ?localidad\n",
+    "WHERE {\n",
+    "    ?localidad <http://dbpedia.org/ontology/isPartOf> <http://dbpedia.org/resource/Community_of_Madrid>\n",
+    "}\n",
+    "LIMIT 10"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "However, that query is very verbose because we are using full URIs.\n",
+    "To simplify it, we will make use of SPARQL prefixes:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX dbo: <http://dbpedia.org/ontology/>\n",
+    "PREFIX dbr: <http://dbpedia.org/resource/>\n",
+    "        \n",
+    "SELECT ?localidad\n",
+    "WHERE {\n",
+    "    ?localidad dbo:isPartOf dbr:Community_of_Madrid.\n",
+    "}\n",
+    "LIMIT 10"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "To make sure that the query returned something sensible, we can test it with some python code:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "assert 'localidad' in solution()['columns']\n",
+    "assert len(solution()['tuples']) == 10"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Now that you have some experience under your belt, it is time to design your own query.\n",
+    "\n",
+    "Your first task it to get a list of Spanish Novelits, using the skeleton below and the previous query to guide you.\n",
+    "\n",
+    "Pages for Spanish novelists are grouped in the *Spanish novelists* DBpedia category. You can use that fact to get your list.\n",
+    "In other words, the difference from the previous query will be using `dct:subject` instead of `dbo:isPartOf`, and `dbc:Spanish_novelists` instead of `dbr:Community_of_Madrid`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "eef1c62e2797bd3ef01f2061da6f83c4",
+     "grade": false,
+     "grade_id": "cell-7a9509ff3c34127e",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "\n",
+    "SELECT ?escritor\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "LIMIT 10"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "5a57d16cb2b53925f6e39fba429b7ef2",
+     "grade": true,
+     "grade_id": "cell-91240ded2cac7b6d",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert len(solution()['columns']) == 1 # We only use one variable, ?escritor\n",
+    "assert len(solution()['tuples']) == 10 # There should be 10 results"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Using more criteria\n",
+    "\n",
+    "We can get more than one property in the same query. Let us modify our query to get the population of the cities as well."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dbo: <http://dbpedia.org/ontology/>\n",
+    "PREFIX dbr: <http://dbpedia.org/resource/>\n",
+    "PREFIX dbp: <http://dbpedia.org/property/>\n",
+    "        \n",
+    "SELECT ?localidad ?pop ?when\n",
+    "\n",
+    "WHERE {\n",
+    "    ?localidad dbo:populationTotal ?pop .\n",
+    "    ?localidad dbo:isPartOf dbr:Community_of_Madrid.\n",
+    "    ?localidad dbp:populationAsOf ?when .\n",
+    "}\n",
+    "\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "assert 'localidad' in solution()['columns']\n",
+    "assert 'http://dbpedia.org/resource/Parla' in solution()['columns']['localidad']\n",
+    "assert ('http://dbpedia.org/resource/San_Sebastián_de_los_Reyes', '75912', '2009') in solution()['tuples']"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Time to try it yourself.\n",
+    "\n",
+    "Get the list of Spanish novelists AND their name (using rdfs:label)."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "9d4193612dea95da2d91762b638ad5e6",
+     "grade": false,
+     "grade_id": "cell-83dcaae0d09657b5",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs:<http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "\n",
+    "SELECT ?escritor ?name\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "LIMIT 10"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "86115c2a8982ad12b7250cf4341ae9c3",
+     "grade": true,
+     "grade_id": "cell-8afd28aada7a896c",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'escritor' in solution()['columns']\n",
+    "assert 'http://dbpedia.org/resource/Eduardo_Mendoza_Garriga' in solution()['columns']['escritor']\n",
+    "assert ('http://dbpedia.org/resource/Eduardo_Mendoza_Garriga', 'Eduardo Mendoza') in solution()['tuples']"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Filtering and ordering"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "In the previous example, we saw that we got what seemed to be duplicated answers.\n",
+    "\n",
+    "This happens because entities can have labels in different languages (e.g. English, Spanish).\n",
+    "To restrict the search to only those results we're interested in, we can use filtering.\n",
+    "\n",
+    "We can also decide the order in which our results are shown.\n",
+    "\n",
+    "For instance, this is how we could use filtering to get only large cities in our example, ordered by population:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dbo: <http://dbpedia.org/ontology/>\n",
+    "PREFIX dbr: <http://dbpedia.org/resource/>\n",
+    "        \n",
+    "SELECT ?localidad ?pop ?when\n",
+    "\n",
+    "WHERE {\n",
+    "    ?localidad dbo:populationTotal ?pop .\n",
+    "    ?localidad dbo:isPartOf dbr:Community_of_Madrid.\n",
+    "    ?localidad dbp:populationAsOf ?when .\n",
+    "    FILTER(?pop > 100000)\n",
+    "}\n",
+    "ORDER BY ?pop\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Note that ordering happens before limits."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "a38cb1aea7b1f01f6b37c088384e0a3d",
+     "grade": true,
+     "grade_id": "cell-cb7b8283568cd349",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "# We still have the biggest city\n",
+    "assert ('http://dbpedia.org/resource/Madrid', '3141991', '2014') in solution()['tuples']\n",
+    "# But the smaller ones are gone\n",
+    "assert 'http://dbpedia.org/resource/Tres_Cantos' not in solution()['columns']['localidad']\n",
+    "assert 'http://dbpedia.org/resource/San_Sebastián_de_los_Reyes' not in solution()['columns']['localidad']"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Now, try filtering to get a list of novelists and their name in Spanish, ordered by name `(FILTER (LANG(?nombre) = \"es\") y ORDER BY`"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "b6aaac8ab30d52a042c1efefbbff7550",
+     "grade": false,
+     "grade_id": "cell-ff3d611cb0304b01",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "\n",
+    "SELECT ?escritor ?nombre\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 1000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "3441fbd2267002acbb0d46d9ce94ba97",
+     "grade": true,
+     "grade_id": "cell-d70cc6ea394741bc",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert len(solution()['tuples']) >= 50\n",
+    "assert 'Adelaida García Morales' in solution()['columns']['nombre']\n",
+    "assert sum(1 for k in solution()['columns']['escritor'] if k == 'http://dbpedia.org/resource/Adelaida_García_Morales') == 1"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Optional"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "From now on, we will focus on our Writers example.\n",
+    "\n",
+    "First, we will search for writers born in the XX century, using the [20th-century Spanish novelists](http://dbpedia.org/page/Category:20th-century_Spanish_novelists) category."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "e3ff089c983be1ae937f254b8d9d229a",
+     "grade": false,
+     "grade_id": "cell-ab7755944d46f9ca",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "# YOUR ANSWER HERE"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "cacdd08a8a267c1173304e319ffff563",
+     "grade": true,
+     "grade_id": "cell-cf3821f2d33fb0f6",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Camilo José Cela' in solution()['columns']['nombre']\n",
+    "assert 'Javier Marías' in solution()['columns']['nombre']\n",
+    "assert all(x > '1850-12-31' and x < '2001-01-01' for x in solution()['columns']['nac'])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "In our last example, we were missing many novelists that are do not have birth information in DBpedia.\n",
+    "\n",
+    "We can specify optional values in a query using the `OPTIONAL` keyword.\n",
+    "When a set of clauses are inside an OPTIONAL group, the SPARQL endpoint will try to use them in the query.\n",
+    "If there are no results for that part of the query, the variables it specifies will not be bound (i.e. they will be empty).\n",
+    "\n",
+    "Using that, let us retrieve all the novelists, their birth and death date (if they are available)."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "f4170cbbf042644e394d1eb9acf12ce3",
+     "grade": false,
+     "grade_id": "cell-254a18dd973e82ed",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT ?escritor ?nombre ?fechaNac ?fechaDef\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 200"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "29c6362adbdb5606e158f696594e1052",
+     "grade": true,
+     "grade_id": "cell-4d6a64dde67f0e11",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Wenceslao Fernández Flórez' in solution()['columns']['nombre']\n",
+    "assert '1879-2-11' in solution()['columns']['fechaNac']\n",
+    "assert '' in solution()['columns']['fechaNac'] # Not all birthdates are defined\n",
+    "assert '' in solution()['columns']['fechaDef'] # Some deathdates are not defined"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Bound"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "We can check whether the optional value for a key was bound in a SPARQL query using `BOUND(?key)`.\n",
+    "\n",
+    "This is very useful for two purposes.\n",
+    "First, it allows us to look for patterns that **do not occur** in the graph, such as missing properties.\n",
+    "For instance, we could search for the authors with missing birth information so we can add it.\n",
+    "Secondly, we can use bound in filters to get conditional filters.\n",
+    "We will explore both uses in this exercise."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Get the list of Spanish novelists that are still alive.\n",
+    "A person is alive if their death date is not defined and the were born less than 100 years ago"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "f3c11121eb0d1328d2f5da3580f8d648",
+     "grade": false,
+     "grade_id": "cell-474b1a72dec6827c",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT ?escritor, ?nombre, year(?fechaNac) as ?nac\n",
+    "\n",
+    "WHERE {\n",
+    "    \n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 1000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "770bbddef5210c28486a1929e4513ada",
+     "grade": true,
+     "grade_id": "cell-46b62dd2856bc919",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Fernando Arrabal' in solution()['columns']['nombre']\n",
+    "assert 'Albert Espinosa' in solution()['columns']['nombre']\n",
+    "for year in solution()['columns']['nac']:\n",
+    "    assert int(year) >= 1918"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Now, get the list of Spanish novelists that died before their fifties (i.e. younger than 50 years old), or that aren't 50 years old yet.\n",
+    "\n",
+    "Hint: you can use boolean logic in your filters (e.g. `&&` and `||`).\n",
+    "\n",
+    "Hint 2: Some dates are not formatted properly, which makes some queries fail when they shouldn't. You might need to convert between different types as a workaround. For instance, you could get the year from a date like this: `year(xsd:dateTime(str(?date)))`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "ed34857649c9a6926eb0a3a0e1d8198d",
+     "grade": false,
+     "grade_id": "cell-ceefd3c8fbd39d79",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT ?escritor, ?nombre, YEAR(?fechaNac) as ?nac, ?fechaDef\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "18bb2d8d586bf4a5231973e69958ab75",
+     "grade": true,
+     "grade_id": "cell-461cd6ccc6c2dc79",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Javier Sierra' in solution()['columns']['nombre']\n",
+    "assert 'http://dbpedia.org/resource/Sanmao_(author)' in solution()['columns']['escritor']"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Finding unique elements"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "In our last example, our results show some authors more than once.\n",
+    "This is because some properties are defined more than once.\n",
+    "For instance, birth date is giving using different formats.\n",
+    "Even if we exclude that property from our results by not adding it in our `SELECT`, we will get duplicated lines.\n",
+    "\n",
+    "To solve this, we can use the `DISTINCT` keyword."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Modify your last query to remove duplicated lines.\n",
+    "In other words, authors should only appear once."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "34163ddb0400cd8ddd2c2e2cdf29c20b",
+     "grade": false,
+     "grade_id": "cell-2a39adc71d26ae73",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT DISTINCT ?escritor, ?nombre, year(?fechaNac) as ?nac\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "84ab7d64a45e03e6dd902216a2aad030",
+     "grade": true,
+     "grade_id": "cell-542e0e36347fd5d1",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Javier Sierra' in solution()['columns']['nombre']\n",
+    "assert 'http://dbpedia.org/resource/Albert_Espinosa' in solution()['columns']['escritor']\n",
+    "\n",
+    "from collections import Counter\n",
+    "c = Counter(solution()['columns']['nombre'])\n",
+    "for count in c.values():\n",
+    "    assert count == 1\n",
+    "    \n",
+    "c1 = Counter(solution()['columns']['escritor'])\n",
+    "assert all(count==1 for count in c1.values())\n",
+    "# c = Counter(solution()['columns']['nombre'])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Using other resources"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Get the list of living Spanish novelists born in Madrid.\n",
+    "\n",
+    "Hint: use `dbr:Madrid` and `dbo:birthPlace`"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "25c8edcee216d536aac98fc9aa2b6422",
+     "grade": false,
+     "grade_id": "cell-d175e41da57c889b",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbr:<http://dbpedia.org/resource/>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT DISTINCT ?escritor, ?nombre, ?lugarNac, year(?fechaNac) as ?nac\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "443608e177f514f2cddafa6c1d1e3cc7",
+     "grade": true,
+     "grade_id": "cell-fadd095862db6bc8",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'José Ángel Mañas' in solution()['columns']['nombre']\n",
+    "assert 'http://dbpedia.org/resource/Madrid' in solution()['columns']['lugarNac']\n",
+    "MADRID_QUERY = solution()['columns'].copy()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Traversing the graph"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Get the list of works of the authors in the previous query (i.e. authors born in Madrid), if they have any.\n",
+    "\n",
+    "Hint: use `dbo:author`, which is a **property of a literary work** that points to the author."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "c1f22b82c4d0bd4102a6c38f7f933dc6",
+     "grade": false,
+     "grade_id": "cell-e4b99af9ef91ff6f",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbr:<http://dbpedia.org/resource/>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT DISTINCT ?escritor, ?nombre, ?obra\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 10000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "51acaeb26379c6bd2f8c767001ef79ec",
+     "grade": true,
+     "grade_id": "cell-68661b73c2140e4f",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'http://dbpedia.org/resource/A_Heart_So_White' in solution()['columns']['obra']\n",
+    "assert 'http://dbpedia.org/resource/Tomorrow_in_the_Battle_Think_on_Me' in solution()['columns']['obra']\n",
+    "assert '' in solution()['columns']['obra'] # Some authors don't have works in dbpedia"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Traversing the graph"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Get a list of living Spanish novelists born in Madrid, their name in Spanish, a link to their foto and a website (if they have one).\n",
+    "\n",
+    "If the query is right, you should see a list of writers after running the test code.\n",
+    "\n",
+    "Hint: `foaf:depiction` and `foaf: homepage`"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "e3f8e18a006a763f5cdbe49c97b73f5f",
+     "grade": false,
+     "grade_id": "cell-b1f71c67dd71dad4",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbr:<http://dbpedia.org/resource/>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT ?escritor ?web ?foto\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "ORDER BY ?nombre\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "2d40e7ceb7774b29a709092ee8dfa9f5",
+     "grade": true,
+     "grade_id": "cell-8b8ba7cca701c652",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "fotos = set(filter(lambda x: x != '', solution()['columns']['foto']))\n",
+    "assert len(fotos) > 2\n",
+    "show_photos(fotos) #show the pictures of the writers!"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Union"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "We can merge the results of several queries, just like using `JOIN` in SQL.\n",
+    "The keyword in SPARQL is `UNION`, because we are merging graphs.\n",
+    "\n",
+    "`UNION` is useful in many situations.\n",
+    "For instance, when there are equivalent properties, or when you want to use two search terms and FILTER would be too inefficient.\n",
+    "\n",
+    "The syntax is as follows:\n",
+    "\n",
+    "```sparql\n",
+    "SELECT ?title\n",
+    "WHERE  {\n",
+    "  { ?book dc10:title  ?title }\n",
+    "  UNION\n",
+    "  { ?book dc11:title  ?title }\n",
+    "  \n",
+    "  ... REST OF YOUR QUERY ...\n",
+    "\n",
+    "}\n",
+    "```\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Using UNION, get a list of distinct spanish novelists AND poets.\n",
+    "\n",
+    "Hint: Category: Spanish_poets"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "9c0da379841474601397f5623abc6a9c",
+     "grade": false,
+     "grade_id": "cell-21eb6323b6d0011d",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbr:<http://dbpedia.org/resource/>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT DISTINCT ?escritor, ?nombre\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 10000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "f22c7db423410fcf3e8fce4ec0a8e9f9",
+     "grade": true,
+     "grade_id": "cell-004e021e877c6ace",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Garcilaso de la Vega' in solution()['columns']['nombre']"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "You can also get the count of results either by inspecting the result (we will not cover this) or by aggregating the results using the `COUNT` operation.\n",
+    "\n",
+    "The syntax is:\n",
+    "    \n",
+    "```sparql\n",
+    "SELECT COUNT(?variable) as ?count_name\n",
+    "```\n",
+    "\n",
+    "Try it yourself with our previous example:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "cd7ce9212f587afe311c7631b3908de2",
+     "grade": false,
+     "grade_id": "cell-e35414e191c5bf16",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql http://dbpedia.org/sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbr:<http://dbpedia.org/resource/>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "# YOUR ANSWER HERE\n",
+    "\n",
+    "WHERE {\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "LIMIT 10000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "68609fa02dcf7480e16f0e5eb7849e65",
+     "grade": true,
+     "grade_id": "cell-7a7ef8255a5662e2",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert len(solution()['columns']) == 1\n",
+    "column_name = list(solution()['columns'].keys())[0]\n",
+    "assert int(solution()['columns'][column_name][0]) > 200"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Additional exercises"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Find out if there are more dbpedia entries for writers (dbo:Writer) than for football players (dbo:SoccerPlayers)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Get a list of European countries with a population higher than 20 million, in decreasing order of population, including their URI, name in English and population."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Find the country in the world that speaks the most languages. Show its name in Spanish, if available."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## References"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "* [RDFLib documentation](https://rdflib.readthedocs.io/en/stable/).\n",
+    "* [Wikidata Query Service query examples](https://www.wikidata.org/wiki/Wikidata:SPARQL_query_service/queries/examples)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Licence\n",
+    "The notebook is freely licensed under under the [Creative Commons Attribution Share-Alike license](https://creativecommons.org/licenses/by/2.0/).  \n",
+    "\n",
+    "© 2018 Universidad Politécnica de Madrid."
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.8.1"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}
diff --git a/lod/04_SPARQL_Advanced.ipynb b/lod/04_SPARQL_Advanced.ipynb
new file mode 100644
index 0000000..20d399b
--- /dev/null
+++ b/lod/04_SPARQL_Advanced.ipynb
@@ -0,0 +1,661 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "7276f055a8c504d3c80098c62ed41a4f",
+     "grade": false,
+     "grade_id": "cell-0bfe38f97f6ab2d2",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "<header style=\"width:100%;position:relative\">\n",
+    "  <div style=\"width:80%;float:right;\">\n",
+    "    <h1>Course Notes for Learning Intelligent Systems</h1>\n",
+    "    <h3>Department of Telematic Engineering Systems</h3>\n",
+    "    <h5>Universidad Politécnica de Madrid</h5>\n",
+    "  </div>\n",
+    "        <img style=\"width:15%;\" src=\"../logo.jpg\" alt=\"UPM\" />\n",
+    "</header>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "bd478e6253226d24ba7f33cb9f6ba706",
+     "grade": false,
+     "grade_id": "cell-0cd673883ee592d1",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "## Advanced SPARQL\n",
+    "\n",
+    "This notebook complements [the SPARQL notebook](./01_SPARQL.ipynb) with some advanced commands.\n",
+    "\n",
+    "If you have not completed the exercises in the previous notebook, please do so before continuing.\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "9ea4fd529653214745b937d5fc4559e5",
+     "grade": false,
+     "grade_id": "cell-10264483046abcc4",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "## Objectives\n",
+    "\n",
+    "* To cover some SPARQL concepts that are less frequently used "
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "2fedf0d73fc90104d1ab72c3413dfc83",
+     "grade": false,
+     "grade_id": "cell-4f8492996e74bf20",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "## Tools\n",
+    "\n",
+    "See [the SPARQL notebook](./01_SPARQL_Introduction.ipynb#Tools)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "c5f8646518bd832a47d71f9d3218237a",
+     "grade": false,
+     "grade_id": "cell-eb13908482825e42",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "Run this line to enable the `%%sparql` magic command."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from helpers import *"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Exercises"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Working with dates"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "To explore dates, we will focus on our Writers example.\n",
+    "\n",
+    "First, search for writers born in the XX century.\n",
+    "You can use a special filter, knowing that `\"2000\"^^xsd:date` is the first date of year 2000."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "69e23e6e3dc06ca9d2b5d878c2baba94",
+     "grade": false,
+     "grade_id": "cell-ab7755944d46f9ca",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT ?escritor, ?nombre, year(?fechaNac) as ?nac\n",
+    "\n",
+    "WHERE {\n",
+    "    ?escritor dct:subject dbc:Spanish_novelists .\n",
+    "    ?escritor rdfs:label ?nombre .\n",
+    "    ?escritor dbo:birthDate ?fechaNac .\n",
+    "    FILTER(lang(?nombre) = \"es\") .\n",
+    "    # YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 1000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "211c632634327a1fd805326fa0520cdd",
+     "grade": true,
+     "grade_id": "cell-cf3821f2d33fb0f6",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Camilo José Cela' in solution()['columns']['nombre']\n",
+    "assert 'Javier Marías' in solution()['columns']['nombre']\n",
+    "assert all(int(x) > 1899 and int(x) < 2001 for x in solution()['columns']['nac'])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Now, get the list of Spanish novelists that are still alive.\n",
+    "\n",
+    "A person is alive if their death date is not defined and the were born less than 100 years ago.\n",
+    "\n",
+    "Remember, we can check whether the optional value for a key was bound in a SPARQL query using `BOUND(?key)`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "e4579d551790c33ba4662562c6a05d99",
+     "grade": false,
+     "grade_id": "cell-474b1a72dec6827c",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT ?escritor, ?nombre, year(?fechaNac) as ?nac\n",
+    "\n",
+    "WHERE {\n",
+    "    ?escritor dct:subject dbc:Spanish_novelists .\n",
+    "    ?escritor rdfs:label ?nombre .\n",
+    "    ?escritor dbo:birthDate ?fechaNac .\n",
+    "# YOUR ANSWER HERE\n",
+    "    FILTER(lang(?nombre) = \"es\") .\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 1000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "770bbddef5210c28486a1929e4513ada",
+     "grade": true,
+     "grade_id": "cell-46b62dd2856bc919",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Fernando Arrabal' in solution()['columns']['nombre']\n",
+    "assert 'Albert Espinosa' in solution()['columns']['nombre']\n",
+    "for year in solution()['columns']['nac']:\n",
+    "    assert int(year) >= 1918"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Working with badly formatted dates (OPTIONAL!)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Now, get the list of Spanish novelists that died before their fifties (i.e. younger than 50 years old), or that aren't 50 years old yet.\n",
+    "\n",
+    "For the sake of simplicity, you can use the `year(<date>)` function.\n",
+    "\n",
+    "Hint: you can use boolean logic in your filters (e.g. `&&` and `||`).\n",
+    "\n",
+    "Hint 2: Some dates are not formatted properly, which makes some queries fail when they shouldn't. As a workaround, you could convert the date to string, and back to date again: `xsd:dateTime(str(?date))`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "2a24f623c23116fd23877facb487dd16",
+     "grade": false,
+     "grade_id": "cell-ceefd3c8fbd39d79",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "SELECT ?escritor, ?nombre, year(?fechaNac) as ?nac, ?fechaDef\n",
+    "\n",
+    "WHERE {\n",
+    "    ?escritor dct:subject dbc:Spanish_novelists .\n",
+    "    ?escritor rdfs:label ?nombre .\n",
+    "    ?escritor dbo:birthDate ?fechaNac .\n",
+    "    # YOUR ANSWER HERE\n",
+    "}\n",
+    "# YOUR ANSWER HERE\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "18bb2d8d586bf4a5231973e69958ab75",
+     "grade": true,
+     "grade_id": "cell-461cd6ccc6c2dc79",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert 'Javier Sierra' in solution()['columns']['nombre']\n",
+    "assert 'http://dbpedia.org/resource/Sanmao_(author)' in solution()['columns']['escritor']"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Regular expressions"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "[Regular expressions](https://www.w3.org/TR/rdf-sparql-query/#funcex-regex) are a very powerful tool, but we will only cover the basics in this exercise.\n",
+    "\n",
+    "In essence, regular expressions match strings against patterns.\n",
+    "In their simplest form, they can be used to find substrings within a variable.\n",
+    "For instance, using `regex(?label, \"substring\")` would only match if and only if the `?label` variable contains `substring`.\n",
+    "But regular expressions can be more complex than that.\n",
+    "For instance, we can find patterns such as: a 10 digit number, a 5 character long string, or variables without whitespaces.\n",
+    "\n",
+    "The syntax of the regex function is the following:\n",
+    "\n",
+    "```\n",
+    "regex(?variable, \"pattern\", \"flags\")\n",
+    "```\n",
+    "\n",
+    "Flags are optional configuration options for the regular expression, such as *do not care about case* (`i` flag).\n",
+    "\n",
+    "As an example, let us find the cities in Madrid that contain \"de\" in their name."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%sparql\n",
+    "\n",
+    "SELECT ?localidad\n",
+    "WHERE {\n",
+    "    ?localidad <http://dbpedia.org/ontology/isPartOf> <http://dbpedia.org/resource/Community_of_Madrid> .\n",
+    "    ?localidad rdfs:label ?nombre .\n",
+    "    FILTER (lang(?nombre) = \"es\" ).\n",
+    "    FILTER regex(?nombre, \"de\", \"i\")\n",
+    "}\n",
+    "LIMIT 10"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Now, use regular expressions to find Spanish novelists whose **first name** is Juan.\n",
+    "In other words, their name **starts with** \"Juan\"."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "6e444c20b411033a6c45fd5a566018fa",
+     "grade": false,
+     "grade_id": "cell-a57d3546a812f689",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbr:<http://dbpedia.org/resource/>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "# YOUR ANSWER HERE\n",
+    "\n",
+    "WHERE {\n",
+    "    {\n",
+    "        ?escritor dct:subject dbc:Spanish_poets .\n",
+    "    }\n",
+    "    UNION {\n",
+    "        ?escritor dct:subject dbc:Spanish_novelists .\n",
+    "    }\n",
+    "    ?escritor rdfs:label ?nombre\n",
+    "    FILTER(lang(?nombre) = \"es\") .\n",
+    "# YOUR ANSWER HERE\n",
+    "}\n",
+    "ORDER BY ?nombre\n",
+    "LIMIT 1000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "66db9abddfafa91c2dc25577457f71fb",
+     "grade": true,
+     "grade_id": "cell-c149fe65008f39a9",
+     "locked": true,
+     "points": 0,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "outputs": [],
+   "source": [
+    "assert len(solution()['columns']['nombre']) > 15\n",
+    "for i in solution()['columns']['nombre']:\n",
+    "    assert 'Juan' in i\n",
+    "assert \"Robert Juan-Cantavella\" not in solution()['columns']['nombre']"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "1be6d6e4d8e74240ef07deffcbe5e71a",
+     "grade": false,
+     "grade_id": "cell-0c2f0113d97dc9de",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "## Group concat"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "c8dbb73a781bd24080804f289a1cea0b",
+     "grade": false,
+     "grade_id": "asdasdasdddddddddddasdasdsad",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "Sometimes, it is useful to aggregate results from form different rows.\n",
+    "For instance, we might want to get a comma-separated list of the names in each each autonomous community in Spain.\n",
+    "\n",
+    "In those cases, we can use the `GROUP_CONCAT` function."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dbo: <http://dbpedia.org/ontology/>\n",
+    "PREFIX dbr: <http://dbpedia.org/resource/>\n",
+    "        \n",
+    "SELECT ?com, GROUP_CONCAT(?name, \",\") as ?places  # notice how we rename the variable\n",
+    "\n",
+    "WHERE {\n",
+    "    ?localidad dbo:isPartOf ?com .\n",
+    "    ?com dbo:type dbr:Autonomous_communities_of_Spain .\n",
+    "    ?localidad rdfs:label ?name .\n",
+    "    FILTER (lang(?name)=\"es\")\n",
+    "}\n",
+    "\n",
+    "ORDER BY ?com\n",
+    "LIMIT 100"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "cell_type": "markdown",
+     "checksum": "e100e2f89c832cf832add62c107e4008",
+     "grade": false,
+     "grade_id": "asdiopjasdoijasdoijasd",
+     "locked": true,
+     "schema_version": 3,
+     "solution": false
+    }
+   },
+   "source": [
+    "Try it yourself, to get a list of works by each of these authors:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "deletable": false,
+    "nbgrader": {
+     "cell_type": "code",
+     "checksum": "9f6e26faab2be98c72fb7a917ac5a421",
+     "grade": false,
+     "grade_id": "cell-2e3de17c75047652",
+     "locked": false,
+     "schema_version": 3,
+     "solution": true
+    }
+   },
+   "outputs": [],
+   "source": [
+    "%%sparql\n",
+    "\n",
+    "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n",
+    "PREFIX dct:<http://purl.org/dc/terms/>\n",
+    "PREFIX dbc:<http://dbpedia.org/resource/Category:>\n",
+    "PREFIX dbr:<http://dbpedia.org/resource/>\n",
+    "PREFIX dbo:<http://dbpedia.org/ontology/>\n",
+    "\n",
+    "# YOUR ANSWER HERE\n",
+    "\n",
+    "WHERE {\n",
+    "    ?escritor dct:subject dbc:Spanish_novelists .\n",
+    "    ?escritor rdfs:label ?nombre .\n",
+    "    ?escritor dbo:birthDate ?fechaNac .\n",
+    "    ?escritor dbo:birthPlace dbr:Madrid .\n",
+    "    OPTIONAL {\n",
+    "        ?obra dbo:author ?escritor .\n",
+    "        ?obra rdfs:label ?titulo .\n",
+    "    }\n",
+    "    OPTIONAL {\n",
+    "        ?escritor dbo:deathDate ?fechaDef .\n",
+    "    }\n",
+    "    FILTER (?fechaNac <= \"2000\"^^xsd:date).\n",
+    "    FILTER (?fechaNac >= \"1918\"^^xsd:date).\n",
+    "    FILTER (!bound(?fechaDef) || (?fechaNac >= \"1918\"^^xsd:date)) .\n",
+    "    FILTER(lang(?nombre) = \"es\") .\n",
+    "    FILTER(!bound(?titulo) || lang(?titulo) = \"en\") .\n",
+    "\n",
+    "}\n",
+    "ORDER BY ?nombre\n",
+    "LIMIT 10000"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## References"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": []
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Licence\n",
+    "The notebook is freely licensed under under the [Creative Commons Attribution Share-Alike license](https://creativecommons.org/licenses/by/2.0/).  \n",
+    "\n",
+    "© 2018 Universidad Politécnica de Madrid."
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.8.1"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}
diff --git a/lod/helpers.py b/lod/helpers.py
index 7798189..e73a0d5 100644
--- a/lod/helpers.py
+++ b/lod/helpers.py
@@ -20,7 +20,9 @@ display_javascript(js, raw=True)
 
 
 def send_query(query, endpoint):
-    FORMATS = ",".join(["application/sparql-results+json", "text/javascript", "application/json"])
+    FORMATS = ",".join(["application/sparql-results+json",
+                        "text/javascript",
+                        "application/json"])
 
     data = {'query': query}
     # b = quote_plus(query)
@@ -33,7 +35,11 @@ def send_query(query, endpoint):
     res = urlopen(r)
     data = res.read().decode('utf-8')
     if res.getcode() == 200:
-        return json.loads(data)
+        try:
+            return json.loads(data)
+        except Exception:
+            print('Got: ', data, file=sys.stderr)
+            raise
     raise Exception('Error getting results: {}'.format(data))
 
 
@@ -60,7 +66,7 @@ def solution():
 def query(query, endpoint=None, print_table=False):
     global LAST_QUERY
 
-    endpoint = endpoint or "http://fuseki.cluster.gsi.dit.upm.es/sitc/"
+    endpoint = endpoint or "http://fuseki.gsi.upm.es/sitc/"
     results = send_query(query, endpoint)
     tuples = to_table(results)
 
diff --git a/lod/upload.sh b/lod/upload.sh
new file mode 100644
index 0000000..01a70a9
--- /dev/null
+++ b/lod/upload.sh
@@ -0,0 +1,53 @@
+#!/bin/sh
+
+# This is a bit messy
+if [ "$#" -lt 1 ]; then
+        graph="http://example.com/sitc/submission/"
+        endpoint="http://fuseki.gsi.upm.es/hotels/data"
+else if [ "$#" -lt 2 ]; then
+        endpoint=$1
+        graph_base="http://example.com/sitc"
+     else
+         if [ "$#" -lt 3 ]; then
+             endpoint=$1
+             graph=$2
+         else
+             echo "Usage: $0 [<endpoint>] [<graph_base_uri>]"
+             echo
+             exit 1
+         fi
+     fi
+fi
+
+
+upload(){
+    name=$1
+    file=$2
+    echo '###'
+    echo "Uploading: $graph"
+    echo "Graph: $graph"
+    echo "Endpoint: $endpoint"
+    curl -X POST \
+         --digest -u admin:$PASSWORD \
+         -H Content-Type:text/turtle \
+         -T "$file" \
+         --data-urlencode graph=$graph_base/$name \
+	 -G $endpoint 
+
+}
+
+
+total=0
+echo -n "Password: "
+read -s PASSWORD
+
+echo "Uploading synthethic"
+upload "synthetic" synthetic/reviews.ttl || exit 1
+
+for i in *.ttl; do
+    identifier=$(echo ${i%.ttl} | md5sum | awk '{print $1}')
+    echo "Uploading $i"
+    upload $identifier $i 
+    total=$((total + 1))
+done
+echo Uploaded $total
diff --git a/rdf/RDF.ipynb b/rdf/RDF.ipynb
index 1dc4938..07c4a6e 100644
--- a/rdf/RDF.ipynb
+++ b/rdf/RDF.ipynb
@@ -6,11 +6,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "1fba29f718bbaa14890b305223712474",
      "grade": false,
      "grade_id": "cell-2bd9e19ffed99f81",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -31,11 +32,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "845cf125f1c5eb7aa3653ef461bffc67",
      "grade": false,
      "grade_id": "cell-51338a0933103db9",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -86,11 +88,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "5c2cccdf6463262a0f8bc89c64f97fb2",
      "grade": false,
      "grade_id": "cell-d8db3c16cee92ac1",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -175,11 +178,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "d2849a6154d4807b405e6ec84601c231",
      "grade": false,
      "grade_id": "cell-14e2327285737802",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -222,11 +226,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "fe9a246ba580c71385e9b83d414a1216",
      "grade": false,
      "grade_id": "cell-a1b60daabb1a9d00",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -240,11 +245,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "63879c425ec11742c95c728a578d109e",
      "grade": false,
      "grade_id": "cell-d9289e96b2b0f265",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -258,11 +264,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "32f1f607adb584aaea9fb90ae4d805b5",
      "grade": false,
      "grade_id": "cell-bb418e9bae1fef1a",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -277,11 +284,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "892f8491591c25defdea5fdcdd289489",
      "grade": false,
      "grade_id": "cell-4a1b60bd9974bbb1",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -295,12 +303,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "a855d3d63be5ea7f73fd85d645b21bfe",
      "grade": true,
      "grade_id": "cell-9ac392294d5708a1",
      "locked": false,
      "points": 0,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -320,11 +329,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "9a73f79f8f282874fb60011e6019e387",
      "grade": false,
      "grade_id": "cell-57f67d1e662b7f09",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -341,11 +351,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "18ad887c2f326ee59139b96860ce8893",
      "grade": false,
      "grade_id": "cell-16214ea73a9b689e",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -359,11 +370,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "ed2466715f57356f22ddeabfb101eb11",
      "grade": false,
      "grade_id": "cell-da88c2f8170436fe",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -382,11 +394,12 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "69182e8fadb9c9751f76786e0fcb8803",
      "grade": false,
      "grade_id": "cell-808cfcbf3891f39f",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -403,11 +416,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "60a9934c544eee9fc2c3745c36beb049",
      "grade": false,
      "grade_id": "cell-1c2ca86de107dec3",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -424,11 +438,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "12b5c7170326932ff3c7e1688a5769b2",
      "grade": false,
      "grade_id": "cell-0154f8481bf393e8",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -444,11 +459,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "b534d998c6d2e9f6bef8c2d88687a96b",
      "grade": false,
      "grade_id": "cell-adc7e6b7e96e8788",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -478,11 +494,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "67540252804835faea83d96aab87aa29",
      "grade": false,
      "grade_id": "cell-e73f1933742f7ab3",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -528,11 +545,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "d6f1bf2230282256e5fcb85dba0eef45",
      "grade": false,
      "grade_id": "cell-3241bf07ae153beb",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -563,11 +581,12 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "44f8be14db3d3e42b5b85f0485206346",
      "grade": false,
      "grade_id": "definition",
      "locked": false,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -594,12 +613,13 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "e8ba71b32e6d4f15aef9dc7fe70387fe",
      "grade": true,
      "grade_id": "cell-2fb6e144a6691ede",
      "locked": true,
      "points": 10,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -615,11 +635,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "75d90c9a83c694f61e51bd5c47a672d9",
      "grade": false,
      "grade_id": "cell-63a55e7b8b195d59",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -633,11 +654,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "23632182da48df109721378408e57f01",
      "grade": false,
      "grade_id": "cell-3843c3ce98a77c56",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -660,11 +682,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "6c4b25718f493ad5964370f412519543",
      "grade": false,
      "grade_id": "cell-f42c087c9065bb23",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -706,12 +729,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "c7af0b9af5a64773785cc890f2431c78",
      "grade": true,
      "grade_id": "cell-c2e5b58ea74e8276",
      "locked": false,
      "points": 1,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -728,11 +752,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "a29112f51cc3299c7cae27841feb7410",
      "grade": false,
      "grade_id": "cell-9bf9c7d7516fae75",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -750,12 +775,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "56a77e133b532997723bf2f8116389e4",
      "grade": true,
      "grade_id": "cell-17508ecf96884653",
      "locked": false,
      "points": 1,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -769,11 +795,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "9311bca044d7057c86dd753f5343e19b",
      "grade": false,
      "grade_id": "cell-d36826d6323c96e8",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -786,12 +813,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "ba7b24b557d627e2665ca31c75c24c23",
      "grade": true,
      "grade_id": "cell-17508ecf96884655",
      "locked": false,
      "points": 1,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -805,11 +833,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "853651c95cbcd69cd5f495f03d29d19a",
      "grade": false,
      "grade_id": "cell-e25a0db3fe8a6b4b",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -822,12 +851,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "779f0f750508eb52b2d98b92689e426b",
      "grade": true,
      "grade_id": "cell-30797c9ac87cc7e1",
      "locked": false,
      "points": 1,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -841,11 +871,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "f8fff644855ca50a5219598322aa9b32",
      "grade": false,
      "grade_id": "cell-33862c8e38173d9c",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -858,12 +889,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "8ef0ebd54eefb44ff7019f17f58be3ec",
      "grade": true,
      "grade_id": "cell-17508ecf96884657",
      "locked": false,
      "points": 1,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -877,11 +909,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "33e1ec78415c85a795e86211d88316c2",
      "grade": false,
      "grade_id": "cell-5f922dc14ad3236a",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -894,12 +927,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "b5f208a95a8803e97f82c5f2cdf319dd",
      "grade": true,
      "grade_id": "answer-missing",
      "locked": false,
      "points": 1,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -913,11 +947,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "26eb04e562aa6c7d29efa8318982a337",
      "grade": false,
      "grade_id": "cell-7a3c1553c4d6a9b7",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -961,12 +996,13 @@
    "metadata": {
     "deletable": false,
     "nbgrader": {
+     "cell_type": "code",
      "checksum": "bf8d215c42321236b783601e7d072a05",
      "grade": true,
      "grade_id": "cell-ff2413f45311f086",
      "locked": false,
      "points": 0,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": true
     }
    },
@@ -981,11 +1017,12 @@
     "deletable": false,
     "editable": false,
     "nbgrader": {
+     "cell_type": "markdown",
      "checksum": "cffc12120c51a7d994063f66d788570a",
      "grade": false,
      "grade_id": "cell-ec8df1a53c3d3f23",
      "locked": true,
-     "schema_version": 1,
+     "schema_version": 3,
      "solution": false
     }
    },
@@ -1027,7 +1064,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.2"
+   "version": "3.8.1"
   }
  },
  "nbformat": 4,