Hi, my name is Steve Howell, and I have been programming in Python more or less full time since 2001.

In 2010 I attempted to submit a patch to CPython shown here: ProposalToSpeedUpListOperations

I mainly use Python at work now, but I have also contributed to open source projects.  Here are some things that I've done in the Open Source world:

    http://gvr.sourceforge.net/ (Guido van Robot learning IDE)
  
    the initial version of LocalSiteMap feature in MoinMoin

Here is an early version of the code on the SimplePrograms page.  I wrote most of the initial code, with helpful edits from other folks.

I am keeping it here for posterity.  The code below is free for use under the Python license.  I encourage you to try building up your own suite of examples.

One thing unique about the format below is that each program gets one line longer than the previous.

All of this code has been tested on 2.4 or 2.5.

{{{
    ------ 1 Output
    print 'hello world'

    ------ 2 Looping
    for name in ['peter', 'paul', 'mary']:
        print name

    ------ 3 Input, comments
    # This is a Python comment. \n is a newline
    name = raw_input('What is your name?\n')
    print 'Hi', name

    ------ 4 Fibonacci, tuple assignment
    parent_rabbits, baby_rabbits = (1, 1)
    while baby_rabbits < 100:
        print 'This generation has %d rabbits' % baby_rabbits
        parent_rabbits, baby_rabbits = (baby_rabbits, parent_rabbits + baby_rabbits)

    ------ 5 Functions
    def greet(name):
        print 'hello', name
    greet('Jack')
    greet('Jill')
    greet('Bob')

    ------ 6 Import, regular expresssions
    import re
    for test_string in [ '555-1212', 'ILL-EGAL']:
        if re.match('\d\d\d-\d\d\d\d$', test_string):
            print test_string, 'is a valid US local phone number'
        else:
            print test_string, 'rejected'

    ------ 7 Dictionaries, generator expressions
    prices = {'apple': 0.40, 'banana': 0.50}
    my_purchase = {
        'apple': 1,
        'banana': 6}
    grocery_bill = sum(prices[fruit] * my_purchase[fruit]
                       for fruit in my_purchase)
    print 'I owe the grocer $%.2f' % grocery_bill


    ------ 8 Command line arguments, exception handling
    #!/usr/local/bin/python
    # This program adds up integers in the command line
    import sys
    try:
        total = sum(int(arg) for arg in sys.argv[1:])
        print 'sum =', total
    except ValueError:
        print 'Please supply integer arguments'


    ------ 9 Opening files
    # indent your Python code to put into an email
    import glob
    # glob supports Unix style pathname extensions
    python_files = glob.glob('*.py')
    for fn in sorted(python_files):
        print '    ------'
        for line in open(fn):
            print '    ' + line.rstrip()
        print

    ------ 10 Time, conditionals
    import time
    now = time.localtime()
    hour = now.tm_hour
    if hour < 8: print 'sleeping'
    elif hour < 9: print 'commuting'
    elif hour < 17: print 'working'
    elif hour < 18: print 'commuting'
    elif hour < 20: print 'eating'
    elif hour < 22: print 'resting'
    else: print 'sleeping'

    ------ 11 Triple-quoted strings, while loop
    REFRAIN = '''
    %d bottles of beer on the wall,
    %d bottles of beer,
    take one down, pass it around,
    %d bottles of beer on the wall!
    '''
    bottles_of_beer = 99
    while bottles_of_beer > 1:
        print REFRAIN % (bottles_of_beer, bottles_of_beer,
            bottles_of_beer - 1)
        bottles_of_beer -= 1

    ------ 12 List slicing
    def sieve_of_eratosthenes(candidates):
        i = 0
        while True:
            divisor = candidates[i]
            if divisor * divisor > candidates[-1]:
                return candidates
            else:
                i += 1
            candidates = candidates[:i] + \
                [num for num in candidates[i:]
                    if num % divisor != 0]
    print sieve_of_eratosthenes(range(2,100))

    ------ 13 Unit testing
    # Let's write reusable code, and unit test it.
    def add_money(amounts):
        # do arithmetic in pennies so as not to accumulate float errors
        pennies = sum([round(int(amount * 100)) for amount in amounts])
        return float(pennies / 100.0)
    if __name__ == '__main__':
        import unittest
        class TestAddMoney(unittest.TestCase):
            def test_float_errors(self):
                self.failUnlessEqual(add_money([0.13, 0.02]), 0.15)
                self.failUnlessEqual(add_money([100.01, 99.99]), 200)
                self.failUnlessEqual(add_money([0, -13.00, 13.00]), 0)
        unittest.main()

    ------ 14 Classes
    class BankAccount:
        def __init__(self, initial_balance = 0):
            self.balance = initial_balance
        def deposit(self, amount):
            self.balance += amount
        def withdraw(self, amount):
            self.balance -= amount
        def overdrawn(self):
            return self.balance < 0
    my_account = BankAccount()
    my_account.deposit(15)
    my_account.withdraw(5)
    print my_account.balance
    print my_account.overdrawn()

    ------ 15 itertools
    import itertools
    lines = '''
    This is the
    first paragraph.

    This is the second.
    '''.splitlines()
    # Use itertools.groupby and bool to return groups of
    # consecutive lines that either have content or don't.
    for has_chars, frags in itertools.groupby(lines, bool):
        if has_chars:
            print ' '.join(frags)
    # PRINTS:
    # This is the first paragraph.
    # This is the second.

}}}



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