在带有Tastypie的Django中，无法让order_by与关系一起工作

from tastypie.resources import ModelResource, ALL, ALL_WITH_RELATIONS
from tastypie.exceptions import BadRequest

class CustomSortingResource(ModelResource):
    def apply_sorting(self, obj_list, options=None):
        if options and 'order_by' in options:
            order_by = options['order_by']
            if 'relation_field' in order_by:
                # 自定义关系字段排序逻辑
                # 这里可以使用Django的ORM进行排序操作
                # 例如：obj_list = obj_list.order_by('relation_field__field_to_sort')
                pass
            else:
                # 使用Tastypie默认的排序逻辑
                return super(CustomSortingResource, self).apply_sorting(obj_list, options)
        return obj_list

class MyResource(CustomSortingResource):
    class Meta:
        queryset = MyModel.objects.all()
        resource_name = 'my_resource'
        ordering = ['field_to_sort']
        filtering = {
            'relation_field': ALL_WITH_RELATIONS,
        }