def test_iter(self):
        prio_set_list = event._PrioritizedSetList()
        objs = [(i,) for i in range(5)]
        for i, obj in enumerate(objs):
            prio_set_list.add(-i, obj)

        for i, set_ in enumerate(prio_set_list):
            assert set_ == (-i, {objs[i]})
def get_level(self, level, queue):
		if queue == None:
			queue = []
		if level == 1:
			queue.push(self)
		else:
			if self.lchild != None:
				self.lchild.get_level(level-1, queue)
			if self.rchild != None:
				self.rchild.get_level(level-1, queue)
		return queue