Python 使用表中的字段作为条件创建ManyToManyField

这就是我想要实现的目标：

class Event(Model):
    attendees = ManyToManyField(User, through='Involvement', related_name='attended_events')
    interested_users = ManyToManyField(User, through='Involvement', related_name='interested_in_events')
    organizers = ManyToManyField(User, through='Involvement', related_name='organized_events')

class Involvement(Model):
    event = ForeignKey(Event, CASCADE)
    user = ForeignKey(User, CASCADE)
    involvement = CharField(choices=(('INTERESTED', 'Interested'), ('ATTENDED', 'Attended'), ('ORGANIZED', 'Organized')))

我收到的错误是：

 The model has three identical many-to-many relations through the intermediate model 'app.ActivityInvolvement'.

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我知道

limit\u choices\u to

在很多领域都不起作用，如果不创建具有相同结构的3个直通表，我该如何实现这一点？

为什么需要直通表？为什么没有三个完全独立的m2m字段？也许会有帮助。