mongo4.2环境下，

执行这句代码报错：

        updated_obj = cls.objects(prefix=id_prefix).modify(set__prefix=id_prefix, inc__current=1, upsert=True, new=True)

错误信息：

mongoengine.errors.OperationError: Update failed (BSON field 'no_cursor_timeout' is an unknown field., full error: {'ok': 0.0, 'errmsg': "BSON field 'no_cursor_timeout' is an unknown field.", 'code': 51177, 'codeName': 'Location51177'})

版本降级可破，降到了3.2

https://github.com/MongoEngine/mongoengine/issues/2148

https://github.com/MongoEngine/mongoengine/pull/2160