https://blog.wongcw.com/2018/12/01/go-%e8%aa%9e%e8%a8%80%e7%9a%84%e4%b8%8b%e4%b8%80%e5%80%8b%e5%a4%a7%e7%89%88%e6%9c%ac%ef%bc%9ago-2-0-%e8%a2%ab%e5%ae%89%e6%8e%92%e4%b8%8a%e4%ba%86/