'str' object has no attribute 'resolve_expression'

django 操作数据库时报错：'str' object has no attribute 'resolve_expression'

public_obj = PublicTemplate.objects.filter(version=version)
key_obj=public_obj.values(newname=keyname)

　　解决办法：将

public_obj.values(newname=keyname)
更改为：

public_obj.filter(newname=keyname)