def _failed_join_report(self):
    return (res for res in self.results if (res.backend.is_cached(res.id) and (res.state in states.PROPAGATE_STATES)))
def _failed_join_report(self):
    return (res for res in self.results if (res.backend.is_cached(res.id) and (res.state in states.PROPAGATE_STATES)))