message: Pipe through warm_start_from parameter
diff: @@ -1759,7 +1759,8 @@ class TPUEstimator(estimator_lib.Estimator):
  train_batch_size=None,
  eval_batch_size=None,
  predict_batch_size=None,
  - batch_axis=None):
  + batch_axis=None,
  + warm_start_from=None):
  """Constructs an `TPUEstimator` instance.
  Args:
  @@ -1798,6 +1799,12 @@ class TPUEstimator(estimator_lib.Estimator):
  and per_host_input_for_training is True, batches will be sharded based
  on the major dimension. If tpu_config.per_host_input_for_training is
  False or `PER_HOST_V2`, batch_axis is ignored.
  + warm_start_from: Optional string filepath to a checkpoint or SavedModel to
  + warm-start from, or a `tf.estimator.WarmStartSettings`
  + object to fully configure warm-starting. If the string
  + filepath is provided instead of a `WarmStartSettings`,
  + then all variables are warm-started, and it is assumed
  + that vocabularies and Tensor names are unchanged.
  Raises:
  ValueError: `params` has reserved keys already.
  @@ -1850,7 +1857,8 @@ class TPUEstimator(estimator_lib.Estimator):
  model_fn=model_function,
  model_dir=model_dir,
  config=config,
  - params=params)
  + params=params,
  + warm_start_from=warm_start_from)
  self._iterations_per_training_loop = (
  self._config.tpu_config.iterations_per_loop)
  