message: Use public DistributedDataset symbol
diff: @@ -1542,7 +1542,4 @@ def _scipy_sparse_to_sparse_tensor(t):
  def _is_distributed_dataset(ds):
  - # TODO(b/151165986): Use public APIs.
  - return isinstance(
  - ds,
  - (input_lib.DistributedDataset, input_lib.DistributedDatasetsFromFunction))
  + return isinstance(ds, input_lib.DistributedDatasetInterface)
  