docs: def format_exception(etype, value, tback, limit=None):
      """
      Python 2 compatible version of traceback.format_exception
      Accepts negative limits like the Python 3 version
      """
  
      rtn = ['Traceback (most recent call last):\n']
  
      if limit is None or limit >= 0:
          rtn.extend(traceback.format_tb(tback, limit))
      else:
          rtn.extend(traceback.format_list(traceback.extract_tb(tback)[limit:]))
  
      rtn.extend(traceback.format_exception_only(etype, value))
  
      return rtn