message: Fix the api docstrings for on_*_batch_begin methods.
diff: @@ -420,8 +420,9 @@ class CallbackList(object):
  Arguments:
  batch: Integer, index of batch within the current epoch.
  - logs: Dict. Has keys `batch` and `size` representing the current batch
  - number and the size of the batch.
  + logs: Dict, contains the return value of `model.train_step`. Typically,
  + the values of the `Model`'s metrics are returned. Example:
  + `{'loss': 0.2, 'accuracy': 0.7}`.
  """
  # TODO(b/150629188): Make ProgBarLogger callback not use batch hooks
  # when verbose != 1
  @@ -443,8 +444,9 @@ class CallbackList(object):
  Arguments:
  batch: Integer, index of batch within the current epoch.
  - logs: Dict. Has keys `batch` and `size` representing the current batch
  - number and the size of the batch.
  + logs: Dict, contains the return value of `model.test_step`. Typically,
  + the values of the `Model`'s metrics are returned. Example:
  + `{'loss': 0.2, 'accuracy': 0.7}`.
  """
  if self._should_call_test_batch_hooks:
  self._call_batch_hook(ModeKeys.TEST, 'begin', batch, logs=logs)
  @@ -464,8 +466,9 @@ class CallbackList(object):
  Arguments:
  batch: Integer, index of batch within the current epoch.
  - logs: Dict. Has keys `batch` and `size` representing the current batch
  - number and the size of the batch.
  + logs: Dict, contains the return value of `model.predict_step`,
  + it typically returns a dict with a key 'outputs' containing
  + the model's outputs.
  """
  if self._should_call_predict_batch_hooks:
  self._call_batch_hook(ModeKeys.PREDICT, 'begin', batch, logs=logs)
  