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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 get_replies_to(self, msg):
 """ returns all replies to the given message contained in this thread. :param msg: parent message to look up :type msg: :class:`~alot.db.message.Message` :returns: list of :class:`~alot.db.message.Message` or `None` """

        mid = msg.get_message_id()
        msg_hash = self.get_messages()
        for m in msg_hash.keys():
            if m.get_message_id() == mid:
                return msg_hash[m]
        return None