old_contents: class Bad(Exception):
      def __repr__(self):
          raise RuntimeError("I'm a bad class!")
  
  
  def a():
      x = Bad()
      return x
  
  def b():
      x = Bad()
      raise x
  
  a()
  try:
      b()
  except Exception as exc:
      print(exc)
  
new_contents: class Bad(Exception):
      __slots__ = []
  
      def __repr__(self):
          raise RuntimeError("I'm a bad class!")
  
  
  def a():
      x = Bad()
      return x
  
  def b():
      x = Bad()
      raise x
  
  a()
  try:
      b()
  except Exception as exc:
      print(exc)
  
subject: Add __slots__ to satisfy tests (rudimentary_repr is still ordinary __repr__ if __slots__ are there).