In addition, it defines a secondary_keys method to get just the reverse mapping keys.

除此以外，它还定义了一个secondary_keys方法来获取反向映射键。

youdao

In addition, it defines a secondary_keys method to get just the reverse mapping keys.

除此以外，它还定义了一个secondary_keys方法来获取反向映射键。

youdao