That expression, or that value, or that value, literally gets passed back out of that local environment to the value that comes back out of it. So in particular, none none what's solved returns is a pair.

这个表达或者说值，实际上是从那个局部环境中,输出来付给它的,所以solved返回的是一对值，它可以是一对。

麻省理工公开课 - 计算机科学及编程导论课程节选

It could be the pair of none, none, it could be the pair of, you know, whatever the answer was that we put up there. That value comes back out and is now available inside the scope of Barnyard. OK. And Barnyard then uses that. Question?

也可以是，你知道，任何我们在这里得到的答案,这个返回的值在Barnyard范围内,就可以使用了,然后Barnyard就使用了这个值,有什么问题吗？

麻省理工公开课 - 计算机科学及编程导论课程节选