message: BUG: classinfo should be tuple
diff: @@ -238,7 +238,7 @@ def _FilterInt(v):
  return _FirstNotNone([_FilterInt(x) for x in v])
  return None if isinstance(
  v,
  - compat.integral_types, tensor_shape.Dimension) else _NotNone(v)
  + (compat.integral_types, tensor_shape.Dimension)) else _NotNone(v)
  def _FilterFloat(v):
  