code: def test_success(self, model_service_worker):
      model_service_worker.sock.accept.return_value = self.accept_result
      model_service_worker.sock.recv.return_value = b""
      with pytest.raises(SystemExit):
          model_service_worker.run_server()
      model_service_worker.sock.accept.assert_called_once()
  
imports: import os
  import socket
  import sys
  from collections import namedtuple
  import mock
  import pytest
  from mock import Mock
  from ts.model_service_worker import TorchModelServiceWorker
  from ts.service import Service
label_desc: Use image node_id 4 for calling the TestRunServer obj's underlying member method code with example usage: obj.test_success(model_service_worker) without return types