Dictionaries are implemented using a magic technique called hashing, which we'll look at a little bit later in the term, which allows us to retrieve keys in constant time.

散列法的内容,此方法可以让我们在线性,时间内检索到键,因此字典的大小并不重要了。

麻省理工公开课 - 计算机科学及编程导论课程节选