Is it possible to tell ModelSerializer not to create data but to update (DRF)?

Question

Django

There is a model:

class MyModel(...):
    first_field = models.ForeignKey(...)
    second_field = models.ForeignKey(...)
    status = models.CharField(max_length=255)

    class Meta:
        unique_together = ('first_field', 'second_filed', 'status')

first_field and second_filed are the primary key for this table.
Serializer:

class MyModelModelSerializer(serializers.ModelSerializer):
    class Meta:
        model = MyModel
        fields = '__all__'

when calling: MyModelModelSerializer(data=request.data, context={'request': request})
Is it possible to understand that the data needs to be updated or created? at the serializer level?

Answer 1

If I'm not mistaken, then just pass instance to the serializer constructor:
Here is an example of a source code from off. repository