gistfile1.py

def generic_wrapper(f):

    print 'entering wrapper function'

    def inner_function():
        print f()
        print 'leaving wrapper'

    return inner_function


@generic_wrapper       # @ is syntactic sugar for wrapper(function)
def some_function():
    return 'inside wrapped function'

some_function()

>>>entering wrapper function
>>>inside wrapped function
>>>leaving wrapper