Python-сообщество

class Foo(models.Model):
    def __init__(self, *args, **kwargs):
        super(Foo, self).__init__(*args, **kwargs)
        if not self.choice_set.filter(name=u'Name'):
            self.choice_set.add(Bar(some=self,
                                    name=u'Name',))
                super(Foo, self).save()
    title = models.CharField()
class Bar(models.Model):
    some = models.ForeignKey(Foo)
    name = models.CharField()

Bar.objects.create(some=self, name=u'Name')