code: func (req *DNSErrorResponse) Error() string {
  	if len(req.Errors) > 0 {
  		errs := []string{}
  		for name, ss := range req.Errors {
  			if len(ss) > 0 {
  				errs = append(errs, fmt.Sprintf("%s: %s", name, strings.Join(ss, ", ")))
  			}
  		}
  		return fmt.Sprintf("dns error: %s (%s)", req.Message, strings.Join(errs, "; "))
  	}
  	return fmt.Sprintf("dns error: %s", req.Message)
  }
docs: // Error formats the DNSerror into a string