def create(self, validated_data):
        """ This is a standard method called indirectly by calling
        'save' on the serializer.

        This method expects the 'parent_field' and 'parent_instance' to
        be included in the Serializer context.
        """
        if self.context.get('parent_field') \
            and self.context.get('parent_instance'):
            validated_data.update({
                self.context.get('parent_field'):
                self.context.get('parent_instance')})
        instance = self.Meta.model(**validated_data)
        instance.full_clean()
        instance.save()
        return instance
This is a standard method called indirectly by calling
        'save' on the serializer.

        This method expects the 'parent_field' and 'parent_instance' to
        be included in the Serializer context.