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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def reply(self, message: typing.Union[int, types.Message]):
 """ Reply to message :param message: :obj:`int` or :obj:`types.Message` :return: self """

        setattr(self, 'reply_to_message_id', message.message_id if isinstance(message, types.Message) else message)
        return self