#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
fn main() {
    assert_eq!(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)).is_loopback(), true);
    assert_eq!(IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0x1)).is_loopback(), true);
}