pub const A: u16 = 1;
pub const NS: u16 = 2;
pub const CNAME: u16 = 5;
pub const SOA: u16 = 6;
pub const PTR: u16 = 12;
pub const MX: u16 = 15;
pub const TXT: u16 = 16;
pub const AAAA: u16 = 28;
pub const SRV: u16 = 33;
pub const ANY: u16 = 255;
