parameters: (message_descriptor, cls)
docstring: Helper for _AddMessageMethods().
docstring_summary: Helper for _AddMessageMethods().
docstring_tokens: Helper for _AddMessageMethods () .
function: def _AddStrMethod(message_descriptor, cls):
    """Helper for _AddMessageMethods()."""
    def __str__(self):
      return text_format.MessageToString(self)
    cls.__str__ = __str__
function_tokens: def _AddStrMethod ( message_descriptor , cls ) : def __str__ ( self ) : return text_format . MessageToString ( self ) cls . __str__ = __str__