added a few dictionary examples

python-cheatsheet.ipynb

@@ -646,7 +646,11 @@
    "outputs": [],
    "source": [
     "# Make an empty dictionary\n",
-    "dict = {}"
+    "d = {}\n",
+    "\n",
+    "# or\n",
+    "\n",
+    "d = dict()"
    ]
   },
   {
@@ -655,8 +659,8 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "dict['word'] = 10  \n",
-    "print(dict)"
+    "d['word'] = 10  \n",
+    "print(d)"
    ]
   },
   {
@@ -665,7 +669,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "dict.keys()"
+    "d.keys()"
    ]
   },
   {