And I have to admit, I did the standard thing you do every time you run across something you don't know about, you go to Wikipedia.

额外的名为self的变量，那么什么是self呢？,我需要承认，我做了大家当碰到，不会的问题都会做的标准的事情。

麻省理工公开课 - 计算机科学及编程导论课程节选