Django模型反向关系具有名称为字符串的字符串

Question

我想实现一个Django Rest Framework视图，该视图返回模型实例对象的依赖关系树。这是该视图的代码：

class RoomTypeDependencies(viewsets.ViewSet):
    def list(self, request, pk):
        room_type = models.RoomType.objects.get(pk=pk)

        dependency_tree = self.get_object_dependencies(room_type)

        return Response(dependency_tree)

    def get_object_dependencies(self, instance):
        fields = instance.__class__._meta.get_fields()
        dependencies_to_return = []
        for field in fields:
            print(field.name)
            if field.__class__.__name__ == 'ManyToOneRel':
                dependency_to_return = []
                dependent_instances = getattr(instance, field.name)
                for dependent_instance in dependent_instances:
                    dependency_to_return.append(self.get_object_dependencies(dependent_instance))
                dependencies_to_return.append({field.__class__.__name__: dependency_to_return})

        return Response({str(instance): dependencies_to_return})

一切似乎都能正常工作，但我希望getattr(instance, field.name)返回与反向关系相对应的从属实例，就像使用model_object_instance.reverse_relationshio_name模式一样，但是它返回一个 RelatedManager 对象代替。就我而言，问题在于我在字符串变量（field.name）中具有反向关系名称。