def test_contains(self):
        prio_set_list = event._PrioritizedSetList()
        obj = object()

        prio_set_list.add(0, obj)
        assert obj in prio_set_list
def __init__(self, path=None, resolver=None):
        self._path = path or ()
        if not resolver:
            resolver = Resolver()
        self._resolver = resolver