http_constant/http_version/
const.rs

1pub const HTTP_VERSION_0_9: &str = "HTTP/0.9";
2pub const HTTP_VERSION_1_0: &str = "HTTP/1.0";
3pub const HTTP_VERSION_1_1: &str = "HTTP/1.1";
4pub const HTTP_VERSION_2: &str = "HTTP/2";
5pub const HTTP_VERSION_3: &str = "HTTP/3";