def _unregister(self, registration):
        assert(isinstance(registration, Registration))
        assert registration.active
        assert(registration.id in self._registrations)

        if not self._transport:
            raise exception.TransportLost()

        request_id = self._request_id_gen.next()

        on_reply = txaio.create_future()
        self._unregister_reqs[request_id] = UnregisterRequest(request_id, on_reply, registration.id)

        msg = message.Unregister(request_id, registration.id)

        self._transport.send(msg)
        return on_reply


# IApplicationSession.register collides with the abc.ABCMeta.register method
# IApplicationSession.register(ApplicationSession)
Called from :meth:`autobahn.wamp.protocol.Registration.unregister`
dataset/ETHPy150Open crossbario/autobahn-python/autobahn/wamp/protocol.py/ApplicationSession._unregister