PyCon 2011: How Dropbox Did It and How Python Helped(pycon.blip.tv)

    # the original slow version
    # 2.87753200531 sec
    def run():
        _md5 = hashlib.md5()
        for i in itertools.repeat("foo", 10000000):
            _md5.update(i)


    # slight change
    # 1.82029104233 sec
    def run():
        _md5 = hashlib.md5()
        update = _md5.update

        for i in itertools.repeat("foo", 10000000):
            update(i)


    # using any()
    # 1.50683498383 sec
    def run():
        _md5 = hashlib.md5()
        any(itertools.imap(_md5.update, itertools.repeat("foo", 10000000)))