class Thing:
    allThings = set()

    def __init__(self):
        self.networkId = None
        self.id = None
        self.type = None

        self.modelUrl = None
        Thing.Add(self)
    
    def update(self, currentTime):
        pass

    @staticmethod
    def Add(thing):
        thing.id = len(Thing.allThings)
        Thing.allThings.add(thing)
    
    def UpdateAll(currentTime):
        for thing in Thing.allThings:
            thing.update(currentTime)