diff --git a/pa3.ipynb b/pa3.ipynb
index d5d6893..a038e3a 100644
--- a/pa3.ipynb
+++ b/pa3.ipynb
@@ -109,6 +109,29 @@
     "We will first start by importing some modules and setting up our IR system class.\n"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "First we'll download some extra files that we need, if we don't already have them:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%bash\n",
+    "\n",
+    "if [[ ! -d \"./data\" ]]\n",
+    "then\n",
+    "    echo \"Missing extra files (this probably means you're running on Google Colab). Downloading...\"\n",
+    "    git clone https://github.com/cs124/pa3-ir.git\n",
+    "    cp -r ./pa3-ir/{data,porter_stemmer.py} .\n",
+    "fi"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -858,4 +881,4 @@
  },
  "nbformat": 4,
  "nbformat_minor": 1
-}
+}
\ No newline at end of file