def test_exception_in_on_failure_is_logged(self):
        self.log_handler.reset()
        failure_event = self.event_class()
        actor_ref = self.FailingOnFailureActor.start(failure_event)
        actor_ref.tell({'command': 'raise exception'})
        failure_event.wait(5)
        self.log_handler.wait_for_message('error', num_messages=2)
        with self.log_handler.lock:
            self.assertEqual(2, len(self.log_handler.messages['error']))
            log_record = self.log_handler.messages['error'][0]
        self.assertEqual(
            actor_ref % 'Unhandled exception in %s:',
            log_record.getMessage())
dataset/ETHPy150Open jodal/pykka/tests/logging_test.py/ActorLoggingTest.test_exception_in_on_failure_is_logged/swapped operands of `%`