class Status:
    def __init__(self):
        self.state = StateOne(self)
    
    def toggle_state(self):
        self.state.update()

    def set_state(self, new):
        self.state = new


class State:
    def __init__(self, status):
        self.status = status
    
    def update(self):
        new_state = self.next_state_class(self.status)
        self.status.set_state(new_state)

    @property
    def next_state_class(self):
        raise NotImplementedError


class StateOne(State):
    @property
    def next_state_class(self):
        return StateTwo


class StateTwo(State):
    @property
    def next_state_class(self):
        return StateOne