for a in v6_set.iter().filter(|a| asn_set.insert(bgp_client.get_asn(**a))).choose_multiple(&mut rng, 12) {
dns_buff += &format!("x{:x}.dnsseed\tIN\tAAAA\t{}\n", i, a);
}
for a in v6_set.iter().filter(|a| asn_set.insert(bgp_client.get_asn(**a))).choose_multiple(&mut rng, 12) {
dns_buff += &format!("x{:x}.dnsseed\tIN\tAAAA\t{}\n", i, a);
}