code: def test_training_time_saved(self):
      self.assertEqual(metrics.GetTrainingTimeSaved(api_label="baz"), 0)
      metrics.AddTrainingTimeSaved(api_label="baz", microseconds=1000)
      self.assertEqual(
          metrics.GetTrainingTimeSaved(api_label="baz"), 1000
      )
  
imports: import os
  from tensorflow.core.framework import summary_pb2
  from tensorflow.core.framework import versions_pb2
  from tensorflow.core.protobuf import fingerprint_pb2
  from tensorflow.python.eager import test
  from tensorflow.python.saved_model.pywrap_saved_model import metrics
label_desc: Use image node_id 8 for calling the MetricsTest obj's underlying member method code with example usage: obj.test_training_time_saved() without return types