關於註解的原則-

今天在看A Byte of Python的時候有句話說得很好
Code tells you how, comments should tell you why.
程式碼告訴你如何，註解告訴你為何


常常有些code可以透過refactor讓code本身可讀性更高，增加註解只是多此一舉。就像文章中說的，如果一開始就想說code主要是給其他programmer看得，其次才是編譯器，那你需要的註解會少很多。"If you write your code to be consumed by other programmers first, and by the compiler second, you may find the need for additional comments to be greatly reduced. "
只剩下原因會需要註解