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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 _add(self, hostport):
 """Creates a peer from the hostport and adds it to the peer heap"""

        peer = self.peer_class(
            tchannel=self.tchannel,
            hostport=hostport,
            on_conn_change=self._update_heap,
        )
        peer.rank = self.rank_calculator.get_rank(peer)
        self._peers[peer.hostport] = peer

        self.peer_heap.add_and_shuffle(peer)