message: Replace space in "Fraction of Zero Values" with _ because using space is illegal and will be auto replaced.
diff: @@ -144,7 +144,7 @@ def add_zero_fraction_summary(tensor, name=None, prefix=None,
  A scalar `Tensor` of type `string` whose contents are the serialized
  `Summary` protocol buffer.
  """
  - name = _get_summary_name(tensor, name, prefix, 'Fraction of Zero Values')
  + name = _get_summary_name(tensor, name, prefix, 'Fraction_of_Zero_Values')
  tensor = nn.zero_fraction(tensor)
  return add_scalar_summary(tensor, name, print_summary=print_summary)
  