message: Fix the python 3 breakage caused by
diff: @@ -109,7 +109,7 @@ def build_standardized_signature_def(input_tensors, output_tensors,
  classes = _get_classification_classes(output_tensors)
  scores = _get_classification_scores(output_tensors)
  if classes is None and scores is None:
  - items = output_tensors.items()
  + items = list(output_tensors.items())
  if items[0][1].dtype == dtypes.string:
  (_, classes), = items
  else:
  