foreach my $ns ( grep {defined} @_ ) {
  if ( _ipv4($ns) || _ipv6($ns) ) {
    push @ip, $ns;
  } else {
    my $defres = ref($self)->new( debug => $self->{debug} );
    $defres->{persistent} = $self->{persistent};
    my $names  = {};
    my $packet = $defres->send( $ns, 'A' );

##</code><code>##

  use Net::DNS::Resolver::Base;
  my $orig= \&Net::DNS::Resolver::Base::nameservers;
  local *Net::DNS::Resolver::Base::nameservers= sub {
    my ($self, @servers)= @_;
    print "Current nameservers value: "
      .join(", ", @{$self->{nameservers}//[]})
      ."\n";
    print "Assigning nameservers: ".join(", ", @servers)."\n"
      if @servers > 1;
    $orig->(@_);
  };

  # and then the rest of your program

##</code><code>##

  use Net::DNS::Resolver;
  Net::DNS::Resolver->tcp_timeout(1);
  Net::DNS::Resolver->udp_timeout(1);

  # remainder of your program

##</code><code>##

sub AUTOLOAD {                          ## Default method
  my ($self) = @_;

  my $name = $AUTOLOAD;
  $name =~ s/.*://;
  croak qq[unknown method "$name"] unless $public_attr{$name};

  no strict 'refs';          ## no critic ProhibitNoStrict
  *{$AUTOLOAD} = sub {
    my $self = shift;
    $self = $self->_defaults unless ref($self);
    $self->{$name} = shift || 0 if scalar @_;
    return $self->{$name};
  };

  goto &{$AUTOLOAD};
}