code: def test_default_job_spec(self):
      self.assertStartsWith(self._job_spec["job_id"], "cloud_fit_")
      self.assertDictContainsSubset(
          {
              "masterConfig": {
                  "imageUri": self._image_uri,
              },
              "args": [
                  "--remote_dir",
                  self._remote_dir,
                  "--distribution_strategy",
                  MULTI_WORKER_MIRRORED_STRATEGY_NAME,
              ],
          },
          self._job_spec["trainingInput"],
      )
  
imports: import os
  import pickle
  import tempfile
  from unittest import mock
  from googleapiclient import discovery
  import tensorflow
  import tensorflow_datasets
  from tensorflow_cloud.tuner import cloud_fit_client
  from tensorflow_cloud.tuner import cloud_fit_utils
  from tensorflow_cloud.utils import google_api_client
label_desc: Use image node_id 4 for calling the CloudFitClientTest obj's underlying member method code with example usage: obj.test_default_job_spec() without return types