code: def Add(self, service, method, request, global_params=None):
          
          # Retrieve the configs for the desired method and service.
          method_config = service.GetMethodConfig(method)
          upload_config = service.GetUploadConfig(method)
  
          # Prepare the HTTP Request.
          http_request = service.PrepareHttpRequest(
              method_config, request, global_params=global_params,
              upload_config=upload_config)
  
          # Create the request and add it to our master list.
          api_request = self.ApiCall(
              http_request, self.retryable_codes, service, method_config)
          self.api_requests.append(api_request)
docs: Add a request to the batch.
  
          Args:
            service: A class inheriting base_api.BaseApiService.
            method: A string indicated desired method from the service. See
                the example in the class docstring.
            request: An input message appropriate for the specified
                service.method.
            global_params: Optional additional parameters to pass into
                method.PrepareHttpRequest.
  
          Returns:
            None