多对多的自我关系和额外的数据,我如何从某个方向选择?

我有一些分层数据,其中每个集合可以有多个成员,并且可以属于多个集合(组)。

以下是模型:

class Set(models.Model):
    ...
    groups = models.ManyToManyField('self', through='Membership', symmetrical=False)
    members = models.ManyToManyField('self', through='Membership', symmetrical=False)

class Membership(models.Model):
    group = models.ForeignKey( Set, related_name='Members' )
    member = models.ForeignKey( Set, related_name='Groups' )
    order = models.IntegerField( default=-1 )

我想知道如何获取集合实例的所有成员或所有组。 我想我可以做到这一点,但这不是很合乎逻辑,谁能告诉我发生了什么,我该怎么做?

# This gives me a set of Sets
# Which seems to be the groups this Set belongs to
set_instance.set_set.all()

# These give me a set of Memberships, not Sets
set_instance.Members.all()
set_instance.Groups.all()

# These they both return a set of Sets
# which seem to be the members of this one
set_instance.members.all()
set_instance.groups.all()