code: func LookupAAAA(host string, server string, c *dns.Client, m *dns.Msg) (addrs []string, err error) {
  	m.SetQuestion(dns.Fqdn(host), dns.TypeAAAA)
  	r, _, err := c.Exchange(m, net.JoinHostPort(server, "53"))
  	if err != nil {
  		return nil, err
  	}
  
  	for _, ans := range r.Answer {
  		if t, ok := ans.(*dns.AAAA); ok {
  			addrs = append(addrs, t.AAAA.String())
  		}
  	}
  
  	return
  }
docs: // AAAA (IPv6) record lookup