Python presentation at APCUG 2013 Regional conference: http://rleevanceapcug.wix.com/apcug-2013-regional

Python_intro

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   "cells": [
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     "cell_type": "heading",
     "level": 1,
     "metadata": {
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       "slide_type": "slide"
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     "source": [
      "Python"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "![Python logo](files/python-logo-master.png)\n",
      "\n",
      "    Catherine Devlin\n",
      "    APCUG 2013 Regional Conference\n",
      "    Sep 15, 2013\n",
      "    http://tinyurl.com/apcug-2013-python-intro"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "A buzzword-enhanced language\n",
      "============================\n",
      "\n",
      "* Open-source\n",
      "* Multi-purpose\n",
      "* Multi-platform\n",
      "* Dynamic\n",
      "* Object-oriented\n",
      "* Highly readable"
     ]
    },
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "What's it look like?"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "target_letter = \"r\"\n",
      "for animal in [\"horse\", \"cat\", \"racoon\", \"duck\"]:\n",
      "    if target_letter in animal:\n",
      "        print(animal + \" contains the letter \" + target_letter)\n",
      "    else:\n",
      "        print(\"sorry, no \" + target_letter + \" in \" + animal)"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "horse contains the letter r\n",
        "sorry, no r in cat\n",
        "racoon contains the letter r\n",
        "sorry, no r in duck\n"
       ]
      }
     ],
     "prompt_number": 11
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Familiar terms\n",
      "--------------\n",
      "\n",
      "`for`, `if`, `else`, etc."
     ]
    },
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Dynamic"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def lots_of(x):\n",
      "    return 3 * x\n",
      "\n",
      "stuff = \"milk \"\n",
      "print(type(stuff))\n",
      "print(lots_of(stuff))\n",
      "stuff = 3\n",
      "print(type(stuff))\n",
      "print(lots_of(stuff))"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "<class 'str'>\n",
        "milk milk milk \n",
        "<class 'int'>\n",
        "9\n"
       ]
      }
     ],
     "prompt_number": 43
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import datetime\n",
      "\n",
      "print(lots_of(datetime.datetime.now()))"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "outputs": [
      {
       "ename": "TypeError",
       "evalue": "unsupported operand type(s) for *: 'int' and 'datetime.datetime'",
       "output_type": "pyerr",
       "traceback": [
        "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
        "\u001b[1;32m<ipython-input-38-61e691416648>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m()\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[1;32mimport\u001b[0m \u001b[0mdatetime\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      2\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 3\u001b[1;33m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mlots_of\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mdatetime\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mdatetime\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mnow\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
        "\u001b[1;32m<ipython-input-37-3b437fd333c5>\u001b[0m in \u001b[0;36mlots_of\u001b[1;34m(x)\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[1;32mdef\u001b[0m \u001b[0mlots_of\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mx\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 2\u001b[1;33m     \u001b[1;32mreturn\u001b[0m \u001b[1;36m3\u001b[0m \u001b[1;33m*\u001b[0m \u001b[0mx\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      3\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      4\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mlots_of\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"milk\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      5\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mlots_of\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m3\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
        "\u001b[1;31mTypeError\u001b[0m: unsupported operand type(s) for *: 'int' and 'datetime.datetime'"
       ]
      }
     ],
     "prompt_number": 38
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Significant whitespace"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "target_letter = \"r\"\n",
      "for animal in [\"horse\", \"cat\", \"racoon\", \"duck\"]:\n",
      "    if target_letter in animal:\n",
      "        print(animal + \" contains the letter \" + target_letter)\n",
      "    else:\n",
      "        print(\"sorry, no \" + target_letter + \" in \" + animal)"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "horse contains the letter r\n",
        "sorry, no r in cat\n",
        "racoon contains the letter r\n",
        "sorry, no r in duck\n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "- No line endings (a line ending *is* a line ending)\n",
      "- Indentation marks blocks\n",
      "- Python interpreter == your eyeball!"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Highly readable"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "target_letter = \"r\"\n",
      "for animal in [\"horse\", \"cat\", \"racoon\", \"duck\"]:\n",
      "    if target_letter in animal:\n",
      "        print(animal + \" contains the letter \" + target_letter)\n",
      "    else:\n",
      "        print(\"sorry, no \" + target_letter + \" in \" + animal)"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "horse contains the letter r\n",
        "sorry, no r in cat\n",
        "racoon contains the letter r\n",
        "sorry, no r in duck\n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Object-oriented"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "animal = \"moose\"\n",
      "animal.upper()"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 13,
       "text": [
        "'MOOSE'"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "class Animal(object):\n",
      "    def eat(self, food):\n",
      "        return \"What yummy \" + food + \"!\"\n",
      "       \n",
      "fido = Animal()\n",
      "fido.eat('dog food')"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 3,
       "text": [
        "'What yummy dog food!'"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Inheritence"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "class Cat(Animal):\n",
      "    def purr(self):\n",
      "        return 'rrrrrrrrrrrrrrrr'\n",
      "\n",
      "agamemnon = Cat()\n",
      "agamemnon.eat('hotdish')"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 4,
       "text": [
        "'What yummy hotdish!'"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "agamemnon.purr()"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 5,
       "text": [
        "'rrrrrrrrrrrrrrrr'"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "fido.purr()"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "ename": "AttributeError",
       "evalue": "'Animal' object has no attribute 'purr'",
       "output_type": "pyerr",
       "traceback": [
        "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[1;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
        "\u001b[1;32m<ipython-input-6-32f565adf250>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m()\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mfido\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mpurr\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
        "\u001b[1;31mAttributeError\u001b[0m: 'Animal' object has no attribute 'purr'"
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Introspection"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "help(\"x\".upper)"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Help on built-in function upper:\n",
        "\n",
        "upper(...)\n",
        "    S.upper() -> str\n",
        "    \n",
        "    Return a copy of S converted to uppercase.\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 29
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "dir(\"x\")"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 30,
       "text": [
        "['__add__',\n",
        " '__class__',\n",
        " '__contains__',\n",
        " '__delattr__',\n",
        " '__dir__',\n",
        " '__doc__',\n",
        " '__eq__',\n",
        " '__format__',\n",
        " '__ge__',\n",
        " '__getattribute__',\n",
        " '__getitem__',\n",
        " '__getnewargs__',\n",
        " '__gt__',\n",
        " '__hash__',\n",
        " '__init__',\n",
        " '__iter__',\n",
        " '__le__',\n",
        " '__len__',\n",
        " '__lt__',\n",
        " '__mod__',\n",
        " '__mul__',\n",
        " '__ne__',\n",
        " '__new__',\n",
        " '__reduce__',\n",
        " '__reduce_ex__',\n",
        " '__repr__',\n",
        " '__rmod__',\n",
        " '__rmul__',\n",
        " '__setattr__',\n",
        " '__sizeof__',\n",
        " '__str__',\n",
        " '__subclasshook__',\n",
        " 'capitalize',\n",
        " 'casefold',\n",
        " 'center',\n",
        " 'count',\n",
        " 'encode',\n",
        " 'endswith',\n",
        " 'expandtabs',\n",
        " 'find',\n",
        " 'format',\n",
        " 'format_map',\n",
        " 'index',\n",
        " 'isalnum',\n",
        " 'isalpha',\n",
        " 'isdecimal',\n",
        " 'isdigit',\n",
        " 'isidentifier',\n",
        " 'islower',\n",
        " 'isnumeric',\n",
        " 'isprintable',\n",
        " 'isspace',\n",
        " 'istitle',\n",
        " 'isupper',\n",
        " 'join',\n",
        " 'ljust',\n",
        " 'lower',\n",
        " 'lstrip',\n",
        " 'maketrans',\n",
        " 'partition',\n",
        " 'replace',\n",
        " 'rfind',\n",
        " 'rindex',\n",
        " 'rjust',\n",
        " 'rpartition',\n",
        " 'rsplit',\n",
        " 'rstrip',\n",
        " 'split',\n",
        " 'splitlines',\n",
        " 'startswith',\n",
        " 'strip',\n",
        " 'swapcase',\n",
        " 'title',\n",
        " 'translate',\n",
        " 'upper',\n",
        " 'zfill']"
       ]
      }
     ],
     "prompt_number": 30
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Handy collections: lists"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "hotdish_ingredients = [\"noodles\", \"tuna\", \"mayo\", \"celery\"]\n",
      "shopping_list = [\"apple\", \"bread\", hotdish_ingredients, \"spinach\"]\n",
      "\n",
      "for buy_me in shopping_list:\n",
      "    print(buy_me)"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "apple\n",
        "bread\n",
        "['noodles', 'tuna', 'mayo', 'celery']\n",
        "spinach\n"
       ]
      }
     ],
     "prompt_number": 32
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Handy collections (2): dictionaries"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "german = {\"cat\": \"Katze\", dog: \"Hund\"}\n",
      "german[\"cat\"]"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 34,
       "text": [
        "'Katze'"
       ]
      }
     ],
     "prompt_number": 34
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "list comprehension"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "name = \"American of Personal Computer User Groups\"\n",
      "initials = [letter for letter in name if letter.isupper()]\n",
      "print(initials)\n",
      "abbrev = \"\".join(initials)\n",
      "print(abbrev)"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "['A', 'P', 'C', 'U', 'G']\n",
        "APCUG\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Rich standard library"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "- formats: `csv`, `json`, `xml.*`...\n",
      "- compression: `zlib`, `zipfile`, `tarfile`, `bz2`...\n",
      "- datastores: `dbm`, `shelve`, `pickle`...\n",
      "- network: `ftplib`, `urllib2`, `smtp`, `SimpleHTTPServer`...\n",
      "- cryptography: `hashlib`\n",
      "- user interfaces: `cmd`, `curses`..."
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "PyPI (the Cheese Shop)"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "http://pypi.python.org\n",
      "\n",
      "34,000 + freely available modules"
     ]
    },
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Libraries make tasks easy"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import requests\n",
      "\n",
      "response = requests.get('http://dma1.org')\n",
      "response.status_code"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 4,
       "text": [
        "200"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "response.content[:100]"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 5,
       "text": [
        "b'<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\\n<HTML>\\n<HEAD>\\n  <LINK REL=\"SHORTCUT '"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import re\n",
      "re.search(\">(APCUG.*?)<\", str(response.content)).group(1)"
     ],
     "language": "python",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 15,
       "text": [
        "'APCUG 2013 Regional Computer Conference'"
       ]
      }
     ],
     "prompt_number": 15
    },
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "What's it used for?"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "- web development\n",
      "- scientific programming\n",
      "- data analysis\n",
      "- GUI tools\n",
      "- systems administration\n",
      "- games"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "Education"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "- Youth: \"Python for Kids\" books, classes\n",
      "- College: MIT\n",
      "- Professionals: Universal \"pidgin\"\n"
     ]
    },
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "How's it used?"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "Socially!"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "- Developed by distributed groups\n",
      "- Code submitted to PyPI\n",
      "- PyCon, PyOhio..."
     ]
    },
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {
      "slideshow": {
       "slide_type": "slide"
      }
     },
     "source": [
      "How to learn it"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {
      "slideshow": {
       "slide_type": "fragment"
      }
     },
     "source": [
      "- https://wiki.python.org/moin/BeginnersGuide\n",
      "- http://docs.python-guide.org\n",
      "- http://learnpython.org\n",
      "- Coursera\n",
      "- PyOhio\n",
      "- [Python Workshop for Women](http://tinyurl.com/cmh-py-workshop)\n",
      "- [email protected]\n",
      "- tinyurl.com/apcug-2013-python-intro"
     ]
    }
   ],
   "metadata": {}
  }
 ]
}