def METHOD_NAME(self):
    """Test that a slow executor does not block the others."""
    self.setUpService()
    # Adding an executor that takes 0.1s to perform anything.
    slow_notifier = Notifier()
    self.service.add_executor(FakeSlowExecutor(slow_notifier, 0.1))
    # First round of operations.
    self.service.enqueue(FakeQueueItem('op 0'))
    gevent.sleep(0.01)
    for notifier in self.notifiers:
        self.assertEqual(notifier.get_notifications(), 1)
    self.assertEqual(slow_notifier.get_notifications(), 0)
    # Second round.
    self.service.enqueue(FakeQueueItem('op 1'))
    gevent.sleep(0.01)
    for notifier in self.notifiers:
        self.assertEqual(notifier.get_notifications(), 2)
    self.assertEqual(slow_notifier.get_notifications(), 0)
    # After 0.1 * #operations, the slow one picked up.
    gevent.sleep(0.25)
    self.assertEqual(slow_notifier.get_notifications(), 2)