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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 create_server(self):
 """ Creates the GRPC server. """

        self.check_port(self.port)

        try:
            # Establish communication grpc
            self.server = grpc.server(ThreadPoolExecutor(max_workers=10))
            self.unity_to_external = UnityToExternalServicerImplementation()
            add_UnityToExternalServicer_to_server(self.unity_to_external, self.server)
            # Using unspecified address, which means that grpc is communicating on all IPs
            # This is so that the docker container can connect.
            self.server.add_insecure_port('[::]:' + str(self.port))
            self.server.start()
            self.is_open = True
        except:
            raise UnityWorkerInUseException(self.worker_id)