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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_rpc(self):
 """Setup RPC server for dfa server."""


        endpoints = RpcCallBacks(self)
        self.server = rpc.DfaRpcServer(self.ser_q, self._host,
                                       self.cfg.dfa_rpc.transport_url,
                                       endpoints,
                                       exchange=constants.DFA_EXCHANGE)