Converting a function to an elementwise function

elementwise.py

def elementwise(fn):
    def newfn(arg):
        if hasattr(arg,'__getitem__'):  # is a Sequence
            return type(arg)(map(fn, arg))
        else:
            return fn(arg)
    return newfn


@elementwise
def compute(x):
    return x**3 - 1

print compute(5)        # prints: 124
print compute([1,2,3])  # prints: [0, 7, 26]
print compute((1,2,3))  # prints: (0, 7, 26)

This snippet is extracted from the blog post Charming Python: Decorators make magic easy by David Mertz.
I keep it here because it could be useful for stuffs I do at work.