From 4dac403cdc97f8976d53fc1d4e1c5dd6304a7afe Mon Sep 17 00:00:00 2001
From: Sebastian Raschka <se.raschka@me.com>
Date: Tue, 29 Apr 2014 09:53:17 -0400
Subject: [PATCH] self assessment

---
 tutorials/scope_resolution_legb_rule.ipynb | 99 +++++++++++++++++++++-
 1 file changed, 95 insertions(+), 4 deletions(-)

diff --git a/tutorials/scope_resolution_legb_rule.ipynb b/tutorials/scope_resolution_legb_rule.ipynb
index c97a1e4..d1370e4 100644
--- a/tutorials/scope_resolution_legb_rule.ipynb
+++ b/tutorials/scope_resolution_legb_rule.ipynb
@@ -62,6 +62,7 @@
       "- [1. LG - Local vs. Global](#section_1)  \n",
       "- [2. LEG - Local, Enclosed, and Global scope](#section_2)  \n",
       "- [3. LEGB - Local, Enclosed, Global, Built-in](#section_3)  \n",
+      "- [Self-assessment exercise](#assessment)\n",
       "- [Conclusion](#conclusion)  \n",
       "- [Solutions](#solutions)"
      ]
@@ -498,8 +499,6 @@
      "input": [
       "a_var = 'global variable'\n",
       "\n",
-      "\n",
-      "\n",
       "def len(in_var):\n",
       "    print('called my len() function')\n",
       "    l = 0\n",
@@ -511,8 +510,7 @@
       "    len_in_var = len(in_var)\n",
       "    print('Input variable is of length', len_in_var)\n",
       "\n",
-      "#a_func('Hello, World!')\n",
-      "    "
+      "#a_func('Hello, World!')"
      ],
      "language": "python",
      "metadata": {},
@@ -550,6 +548,65 @@
       "Since the exact same names can be used to map names to different objects - as long as the names are in different name spaces - there is no problem of reusing the name `len` to define our own length function (this is just for demonstration pruposes, it is NOT recommended). As we go up in Python's L -> E -> G -> B hierarchy, the function `a_func()` finds `len()` already in the global scope first before it attempts"
      ]
     },
+    {
+     "cell_type": "markdown",
+     "metadata": {},
+     "source": [
+      "<a name =\"assessment\"></a>\n",
+      "<br>\n",
+      "<br>"
+     ]
+    },
+    {
+     "cell_type": "markdown",
+     "metadata": {},
+     "source": [
+      "# Self-assessment exercise"
+     ]
+    },
+    {
+     "cell_type": "markdown",
+     "metadata": {},
+     "source": [
+      "Now, after we went through a couple of exercises, let us quickly check where we are. So, one more time: What would the following code print out?"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "a = 'global'\n",
+      "\n",
+      "def outer():\n",
+      "    \n",
+      "    def len(in_var):\n",
+      "        print('called my len() function: ', end=\"\")\n",
+      "        l = 0\n",
+      "        for i in in_var:\n",
+      "            l += 1\n",
+      "        return l\n",
+      "    \n",
+      "    a = 'local'\n",
+      "    \n",
+      "    def inner():\n",
+      "        global len\n",
+      "        nonlocal a\n",
+      "        a += ' variable'\n",
+      "    inner()\n",
+      "    print('a is', a)\n",
+      "    print(len(a))\n",
+      "\n",
+      "\n",
+      "outer()\n",
+      "\n",
+      "print(len(a))\n",
+      "print('a is', a)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [],
+     "prompt_number": 59
+    },
     {
      "cell_type": "markdown",
      "metadata": {},
@@ -559,6 +616,13 @@
       "<br>"
      ]
     },
+    {
+     "cell_type": "markdown",
+     "metadata": {},
+     "source": [
+      "[[go to solution](#solutions)]"
+     ]
+    },
     {
      "cell_type": "markdown",
      "metadata": {},
@@ -675,6 +739,33 @@
      "metadata": {},
      "outputs": [],
      "prompt_number": 9
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "# Execute to run the self-assessment solution\n",
+      "\n",
+      "sol = \"000010100110111101110101011101000110010101110010001010\"\\\n",
+      "\"0000101001001110100000101000001010011000010010000001101001011100110\"\\\n",
+      "\"0100000011011000110111101100011011000010110110000100000011101100110\"\\\n",
+      "\"0001011100100110100101100001011000100110110001100101000010100110001\"\\\n",
+      "\"1011000010110110001101100011001010110010000100000011011010111100100\"\\\n",
+      "\"1000000110110001100101011011100010100000101001001000000110011001110\"\\\n",
+      "\"1010110111001100011011101000110100101101111011011100011101000100000\"\\\n",
+      "\"0011000100110100000010100000101001100111011011000110111101100010011\"\\\n",
+      "\"0000101101100001110100000101000001010001101100000101001100001001000\"\\\n",
+      "\"0001101001011100110010000001100111011011000110111101100010011000010\"\\\n",
+      "\"1101100\"\n",
+      "\n",
+      "sol_str =''.join(chr(int(sol[i:i+8], 2)) for i in range(0, len(sol), 8))\n",
+      "for line in sol_str.split('\\n'):\n",
+      "    print(line)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [],
+     "prompt_number": 58
     }
    ],
    "metadata": {}