code: def set_stop_chars_left(self, stop_chars):
          
          if not isinstance(stop_chars, set):
              raise TypeError("stop_chars should be type set "
                              "but {} was given".format(type(stop_chars)))
  
          self._stop_chars_left = stop_chars
          self._stop_chars = self._stop_chars_left | self._stop_chars_right
docs: Set stop characters for text on left from TLD.
          Stop characters are used when determining end of URL.
  
          :param set stop_chars: set of characters
          :raises: TypeError