message: Import dataset from the internal module
diff: @@ -25,9 +25,9 @@ import inspect
  import six
  -from tensorflow.data import Dataset
  from tensorflow.python.autograph.utils import py_func
  from tensorflow.python.autograph.utils import tensors
  +from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  @@ -244,7 +244,7 @@ def _py_range(start_or_stop, stop, step):
  def enumerate_(s, start=0):
  - if isinstance(s, Dataset):
  + if isinstance(s, dataset_ops.DatasetV2):
  return _tf_dataset_enumerate(s, start)
  return _py_enumerate(s, start)
  