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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 _setup_master(self):
 """ Construct a Router, Broker, and mitogen.unix listener """

        self.broker = mitogen.master.Broker(install_watcher=False)
        self.router = mitogen.master.Router(
            broker=self.broker,
            max_message_size=4096 * 1048576,
        )
        self._setup_responder(self.router.responder)
        mitogen.core.listen(self.broker, 'shutdown', self.on_broker_shutdown)
        mitogen.core.listen(self.broker, 'exit', self.on_broker_exit)
        self.listener = mitogen.unix.Listener(
            router=self.router,
            path=self.unix_listener_path,
            backlog=C.DEFAULT_FORKS,
        )
        self._enable_router_debug()
        self._enable_stack_dumps()