目录
RFC
RFC 2119
RFC
RFC 2119
https://www.ietf.org/rfc/rfc2119.txt
https://datatracker.ietf.org/doc/html/rfc2119
https://zh-style-guide.readthedocs.io/zh_CN/latest/%E5%85%B3%E4%BA%8E%E6%9C%AC%E6%8C%87%E5%8D%97.html#id5