@classmethod
def new(cls, key, mode, IV=None, **kwargs):
    """
        Returns a ciphering object, using the secret key contained in
        the string **key**, and using the feedback mode **mode**, which
        must be one of MODE_* defined in this module.

        If **mode** is MODE_CBC or MODE_CFB, **IV** must be provided and
        must be a string of the same length as the block size. Not
        providing a value of **IV** will result in a ValueError exception
        being raised.
        """
    return cls(key, mode, IV)
