maybe.py

class maybe(object):
    def __init__(self, original):
        self.original = original
    def __getattr__(self, attr):
        if hasattr(self.original, attr):
            return maybe(getattr(self.original, attr))
        return maybe(None)
    def __call__(self):
        return self.original

if __name__ == "__main__":
    import os
    expanduser = maybe(os).path.expanduser()
    print expanduser('~/foo')
    idontexist = maybe(os).foo.bar.baz()
    assert idontexist is None