code: def get_deployment_target(self, project, deployment_group_id, target_id, expand=None):
          
          route_values = {}
          if project is not None:
              route_values['project'] = self._serialize.url('project', project, 'str')
          if deployment_group_id is not None:
              route_values['deploymentGroupId'] = self._serialize.url('deployment_group_id', deployment_group_id, 'int')
          if target_id is not None:
              route_values['targetId'] = self._serialize.url('target_id', target_id, 'int')
          query_parameters = {}
          if expand is not None:
              query_parameters['$expand'] = self._serialize.query('expand', expand, 'str')
          response = self._send(http_method='GET',
                                location_id='2f0aa599-c121-4256-a5fd-ba370e0ae7b6',
                                version='5.1-preview.1',
                                route_values=route_values,
                                query_parameters=query_parameters)
          return self._deserialize('DeploymentMachine', response)
docs: GetDeploymentTarget.
          [Preview API] Get a deployment target by its ID in a deployment group
          :param str project: Project ID or project name
          :param int deployment_group_id: ID of the deployment group to which deployment target belongs.
          :param int target_id: ID of the deployment target to return.
          :param str expand: Include these additional details in the returned objects.
          :rtype: :class:`<DeploymentMachine> <azure.devops.v5_1.task-agent.models.DeploymentMachine>`