def test_bool(self):
        prio_set_list = event._PrioritizedSetList()

        assert bool(prio_set_list) is False

        prio_set_list.add(0, None)
        assert bool(prio_set_list) is True
def get_config(self):
    config = super().get_config()
    config['masked_tokens'] = tuple(self._masked_tokens)
    return config