如何在链接的Django REST模型中更新数据？

Question

如何在链接的Django REST模型中更新数据
这是我的JSON

{
  "doc_type": 1,
  "warehouse": 4,
  "date": "2022-06-09",
  "number": 980,
  "contragent": 2,
  "comment": "testcom;mgment",
  "items": [
    {
      "product": 7,
      "buy_price": "168.00",
      "sell_price": "500.00",
      "quantity": 17
    },
    {
      "product": 8,
      "buy_price": "168.00",
      "sell_price": "500.00",
      "quantity": 17
    }
  ]
}

，我无法更改“项目”字典中的数据 如果我只提交一个“产品”元素，将删除另一个元素吗？例如，如果三个会添加？
这是我目前的目前，记录是没有问题的，但我只能更新“托运诺特”模型

#serialisers.py

class ConsignmentNoteSerializer(serializers.ModelSerializer):
    creator = serializers.HiddenField(default=serializers.CurrentUserDefault())
    doc_type = serializers.IntegerField(read_only=True)
    # contragent_detail = ContragentSerializer(source='contragent', read_only=True)
    items = ConsignmentItemSerializer(many=True)


    class Meta:
        model = ConsignmentNote
        fields = ['doc_type', "warehouse", 'date', 'number', 'contragent', 'comment', 'creator', 'items']
        read_only_fields = ['id' ]


    def create(self, validated_data):
        items = validated_data.pop('items')
        note = ConsignmentNote.objects.create(**validated_data, doc_type = 1)
        for item in items:
            product = item.pop('product')
            item = ConsignmentItem.objects.create(consignmentnote=note, product=product ,**item)
        return note
    
    def update(self, instance, validated_data):
        instance.date = validated_data.pop('date', instance.date)
        instance.comment = validated_data.pop('comment', instance.comment)
        return instance