Add initial version of chapter 10

09_mappings_00_content.ipynb

@@ -1,5 +1,16 @@
 {
  "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "slideshow": {
+     "slide_type": "skip"
+    }
+   },
+   "source": [
+    "**Important**: Click on \"*Kernel*\" > \"*Restart Kernel and Clear All Outputs*\" *before* reading this chapter in [JupyterLab <img height=\"12\" style=\"display: inline-block\" src=\"static/link_to_jp.png\">](https://jupyterlab.readthedocs.io/en/stable/) (e.g., in the cloud on [MyBinder <img height=\"12\" style=\"display: inline-block\" src=\"static/link_to_mb.png\">](https://mybinder.org/v2/gh/webartifex/intro-to-python/master?urlpath=lab/tree/09_mappings_00_content.ipynb))"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {
@@ -8,7 +19,7 @@
     }
    },
    "source": [
-    "# Chapter 8: Mappings & Sets"
+    "# Chapter 9: Mappings & Sets"
    ]
   },
   {