python - 验证在 OTREE 中不起作用，定义了最大值和错误消息，但即便如此也不起作用

Question

我想让参与者不能竞标超过剩余资金。如果前三轮都投了30，下一轮投不超过11​​0。（200-3*30）

运行此程序时我没有收到任何错误，但验证不起作用，错误消息没有弹出。即使第一次投资出价超过200。

我希望为所有轮次编制的总投标不应超过最初给出的预算。

请帮忙

class Constants(BaseConstants):
    name_in_url = 'C'
    players_per_group = None
    num_rounds = 18
    budget = 200


class Subsession(BaseSubsession):
    pass


class Group(BaseGroup):
    pass


class Player(BasePlayer):
    invest = models.IntegerField(
        label="How much would you like to invest in this proposal?",
        min=0
    )
    total_invest = models.IntegerField()


# PAGES


class MyPage(Page):
    form_model = 'player'
    form_fields = ['invest']

    @staticmethod
    def total_invest(player: Player):
        player_in_all_rounds = player.in_all_rounds()
        return sum([p.invest for p in player_in_all_rounds])

    @staticmethod
    def avail_invest(player: Player):
        return Constants.budget - player.total_invest

    @staticmethod
    def invest_error_message(player, value):
        print('value is', value)
        if value > player.avail_invest:
            return 'Cannot invest more than your remaining fund'


class ResultsWaitPage(WaitPage):
    pass

**strong text**
class Results(Page):
    pass


page_sequence = [MyPage]