gistfile1.py

from decorator import decorator
import inspect

@decorator
def deco(f, *a, **kw):
    # set a default keyword arg
    if 'foo' not in kw:
        kw['foo'] = 'bar'
    return f(*a, **kw)

def f(a, b, foo='bleh', foo2='help'):
    pass

f1 = deco(f)

    
print inspect.getargspec(f)
print inspect.getargspec(f1)

f1(1,2)