#!/usr/bin/perl

use feature qw(say);
use Data::Undump;

undef $/;
$data = <>;

$undump = undump($data);

die "'testing' not found!" unless($undump->{'testing'});

say $undump->{'testing'}->{'link'} // (die "'link' not found!");
say $undump->{'testing'}->{'bandwidth'} // (die "'bandwidth not found!");