message: edit 'unsupported operand` when minus type
diff: @@ -576,10 +576,7 @@ class Dimension(object):
  Returns:
  A Dimension whose value is `self` modulo `other`.
  """
  - try:
  other = as_dimension(other)
  - except (TypeError, ValueError):
  - return NotImplemented
  if self._value is None or other.value is None:
  return Dimension(None)
  else:
  @@ -594,10 +591,7 @@ class Dimension(object):
  Returns:
  A Dimension whose value is `other` modulo `self`.
  """
  - try:
  other = as_dimension(other)
  - except (TypeError, ValueError):
  - return NotImplemented
  return other % self
  def __lt__(self, other):
  