Условие, является ли поле A или B обязательным в Django Rest Framework

У меня есть сериализатор, в котором я хотел бы дать возможность отправить НОВЫЙ адрес с POST-запросом ИЛИ указать ID уже существующего адреса. Требуется одно из двух, но сейчас он просит указать оба варианта.

Есть ли возможность добиться того, чтобы он подтверждал условие? 

class OrderSerializer(serializers.ModelSerializer):

class Meta:
    model = Order
    #fields = '__all__'
    exclude = ['in_calculation','canceled',]
address = AdressSerializer()
addressid = serializers.CharField(source='address')
read_only_fields = ['id','user','status','costs','']

Вы можете использовать validate() и настроенный метод create/update следующим образом:

class OrderSerializer(serializers.ModelSerializer):
    address_detail = AddressSerializer(write_only=True, required=False)

    class Meta:
        model = Order
        fields = (
            'address',         # to set from an existing address
            'address_detail',  # to create a whole new address
        )
        extra_kwargs = {
            'address': {'required': False},  # make `address` to optional if your address in model is required.
        }


    def validate(self, attrs):
        # if `address` and `address_detail` are both present or none of them is present
        if bool('address' in attrs) == bool('address_detail' in attrs):
            raise serializers.ValidationError('You can specify exactly one from these two fields.')

        return attrs

    def create(self, validated_data):
        # do custom logic

class OrderSerializer(serializers.ModelSerializer):
    class Meta:
        model = Order
    
        extra_kwargs = {
            'address': {'required': False}, 
        }

        exclude = [] # some fields that should not be shown
        read_only_fields = [] # some fields that should not be edited

    # Add a nested Serializer to add new addresses while creating an order
    address_detail = addressSerializer(required=False)

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        try:
            if "GET" in self.context['request'].method:
                self.fields['client'] = ClientSerializer()
                # ... some Nested Serializers which are ready-only on GET request.
        except KeyError:
            pass
    
    def create(self,validated_data):
        # check for uniqueness of ordernr and clientnr
        try:
            order = Order.objects.get(client=validated_data.get('client'),ordernr=validated_data.get('ordernr'))
            if order:
                raise ValidationError({'ordernr':'Ordernumber and Client-combination already exists'})
        except ObjectDoesNotExist:

            if validated_data.get('address_detail'):
                address_detail = validated_data.pop('address_detail')
                if address_detail: 
                    address, existent = address.objects.get_or_create(**address_detail)
                    order = Order.objects.create(**validated_data, address=address)
            elif validated_data.get('address'):
                order = Order.objects.create(**validated_data)
        return order

    def validate(self, data):
        validationerrors = {}
        print(data)
        # if `address` and `address_detail` are both present or none of them is present
        if bool('address' in data) == bool('address_detail' in data):
        validationerrors['address'] = "You need to specify exactly one from these two fields."   
        # a lot of other validations...
        if validationerrors:
            raise serializers.ValidationError(validationerrors)
        return data
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