def export_estimator_savedmodel(estimator,
                                export_dir_base,
                                serving_input_receiver_fn,
                                assets_extra=None,
                                as_text=False,
                                checkpoint_path=None,
                                strip_default_attrs=False):
  """Export `Estimator` trained model for TPU inference.

  Args:
    estimator: `Estimator` with which model has been trained.
    export_dir_base: A string containing a directory in which to create
      timestamped subdirectories containing exported SavedModels.
    serving_input_receiver_fn: A function that takes no argument and returns a
      `ServingInputReceiver` or `TensorServingInputReceiver`.
    assets_extra: A dict specifying how to populate the assets.extra directory
      within the exported SavedModel, or `None` if no extra assets are needed.
    as_text: whether to write the SavedModel proto in text format.
    checkpoint_path: The checkpoint path to export.  If `None` (the default),
      the most recent checkpoint found within the model directory is chosen.
    strip_default_attrs: Boolean. If `True`, default-valued attributes will be
      removed from the NodeDefs.

  Returns:
    The string path to the exported directory.
  """
  # `TPUEstimator` requires `tpu_config.RunConfig`, so we cannot use
  # `estimator.config`.
  config = tpu_config.RunConfig(model_dir=estimator.model_dir)
  est = TPUEstimator(
      estimator._model_fn,  # pylint: disable=protected-access
      config=config,
      params=estimator.params,
      use_tpu=True,
      train_batch_size=2048,  # Does not matter.
      eval_batch_size=2048,  # Does not matter.
  )
  return est.export_savedmodel(export_dir_base, serving_input_receiver_fn,
                               assets_extra, as_text, checkpoint_path,
                               strip_default_attrs)
Export `Estimator` trained model for TPU inference.

  Args:
    estimator: `Estimator` with which model has been trained.
    export_dir_base: A string containing a directory in which to create
      timestamped subdirectories containing exported SavedModels.
    serving_input_receiver_fn: A function that takes no argument and returns a
      `ServingInputReceiver` or `TensorServingInputReceiver`.
    assets_extra: A dict specifying how to populate the assets.extra directory
      within the exported SavedModel, or `None` if no extra assets are needed.
    as_text: whether to write the SavedModel proto in text format.
    checkpoint_path: The checkpoint path to export.  If `None` (the default),
      the most recent checkpoint found within the model directory is chosen.
    strip_default_attrs: Boolean. If `True`, default-valued attributes will be
      removed from the NodeDefs.

  Returns:
    The string path to the exported directory.
  
src/tpu_estimator.py