Added a warning to creating.ipynb about Mapping attributes: they

can't be used to access STIX object properties.

docs/guide/creating.ipynb

@@ -330,6 +330,20 @@
     "indicator.name"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "-----\n",
+    "### Warning\n",
+    "Note that because these objects are designed to be usable as `Mapping`s, the attributes of that interface retain their mapping meanings and can't be used to access STIX object properties.  This includes the attributes:\n",
+    "- keys\n",
+    "- values\n",
+    "- items\n",
+    "- get\n",
+    "-----"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -1110,21 +1124,21 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3",
+   "display_name": "Python 2",
    "language": "python",
-   "name": "python3"
+   "name": "python2"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 3
+    "version": 2
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython3",
-   "version": "3.6.7"
+   "pygments_lexer": "ipython2",
+   "version": "2.7.15"
   }
  },
  "nbformat": 4,