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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_link(self, peer):
 """ Retrieves a link to the peer :param peer: A Peer description :return: A link to the peer, None if none available """

        assert isinstance(peer, Peer)

        for protocol in self._protocols:
            try:
                # Try to get a link
                return protocol.get_link(peer)

            except ValueError:
                # Peer can't be handled by this protocol
                pass

        # No link found
        return None