code: def build_nested_field(self, field_name, relation_info, nested_depth):
          
          class NestedSerializer(HyperlinkedModelSerializer):
              class Meta:
                  model = relation_info.related_model
                  depth = nested_depth - 1
  
          field_class = NestedSerializer
          field_kwargs = get_nested_relation_kwargs(relation_info)
  
          return field_class, field_kwargs
docs: Create nested fields for forward and reverse relationships.