在python模块中排序类

Question

我在python文件中有以下三个类，显然我在customerOrder（第3行）出现错误，因为它尚未定义 - 类是使用uml到python工具（witchcraftmda）生成的，是否有python模块自动命令类，以便依赖类自动向上移动 - 或任何其他python技巧（我是新手）。

class CustomerSerializer(serializers.ModelSerializer):
    displayName = serializers.ReadOnlyField()
    customerOrder = CustomerOrderSerializer(many=True)

    class Meta:
        model = Customer


class CustomerOrderSerializer(serializers.ModelSerializer):
    displayName = serializers.ReadOnlyField()

    customer = CustomerLookupSerializer

    orderItems = OrderItemSerializer(many=True)

    class Meta:
        model = CustomerOrder


class OrderItemSerializer(serializers.ModelSerializer):
    displayName = serializers.ReadOnlyField()

    customerOrder = CustomerOrderLookupSerializer
    product = ProductLookupSerializer


    class Meta:
        model = OrderItem