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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 notify_peer_message(self, message, sender_id):
 """A new message was received from a peer"""

        payload = message.SerializeToString()
        self._notify(
            "consensus_notifier_notify_peer_message",
            payload,
            len(payload),
            sender_id,
            len(sender_id))