          # at the point of save.
          instance._related_data = related_data
          instance._m2m_data = m2m_data
  
          return instance
  
      def from_native(self, data, files):
 
</s> remove             if field_name in exclusions and not field.read_only:
 </s> add             if field_name in exclusions \
                and not field.read_only \
                and not isinstance(field, Serializer): </s> remove         serializer = OneToOneTargetSerializer(instance, data=data)
 </s> add         serializer = self.Serializer(instance, data=data)
        instance._nested_forward_relations = nested_forward_relations
          # at the point of save.
          instance._related_data = related_data
          instance._m2m_data = m2m_data
        instance._nested_forward_relations = nested_forward_relations
  
          return instance
  
      def from_native(self, data, files):
keep keep add keep keep keep keep
 Cleanup one-one nested tests and implementation 
rest_framework/serializers.py