Django one2one字段上的管理内联线

我有三个django模型，我想在order的页面上编辑item的实例。可能吗

#models.py

class Item(models.Model):
    name = models.CharField(max_length = 128)
    cart = models.ForeignKey('Cart')

class Cart(models.Model):
    number = models.IntegerField()

class Order(models.Model):
    cart = models.OneToOneField('Cart')

#admin.py

ItemInline(admin.TabularInline):
    model = Item

CartInline(admin.TabularInline):
    model = Cart

Order(ModelAdmin):
    inlines = (CartInline,) # I need ItemInline here...

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让订单成为购物车的一部分，而不是相反