Python Patterns

I have now been working with Python for more than a month, here are some of the interesting patterns that I found in the language. Its a nice, clean and easy language, in particular I really enjoy the list comprehensions.

##Lists

###Loop over a list

    for item in items:
        print item

###Loop over a dictionary

    for key, value in dictionaryname.items()

###Map with list comprehensions

    [func(item) for item in items]

###Map over list of lists

    [func(item) for list in lists for item in items]

###Filter list

    [item for item in items if wanted(item)]

###Conditions in list comprehensions

    #increase magnitude
    [item -1 if item < 0 else item + 1 for item in items]

##Modules

###Create a module

Create a folder with a blank file named init.py

###Import classes from modules

    from modulename import ClassName

###Relative import or modules

    from ..packagename import modulename

##Debugging

###Escape in to interpreter

    import code
    code.interact(local=locals())

##Benchmark

###Simple Benchmark

    from time import time
    t1 = time.time()
    function()
    t2 = time.time()
    print t2-t1

##Exceptions

###Raise an exception

    raise Exception("message")

Useful built-in types: ValueError, TypeError, ArithmeticError. Complete List