#!/usr/bin/perl

use strict;
use warnings;
use Net::FTP;

$| = 1;

my $words_all = {
  kosovar => [qw(33 35 28 44)],
};

my %pack;
  
while (my ($word, $url_list) = each %{$words_all}){
  my $url_list_packed = pack 'v*', @{$url_list};
  $pack{$word} = $url_list_packed;
}

warn "calling isa on kosovar\n";
warn UNIVERSAL::isa($pack{'kosovar'}, "ARRAY") . "\n";

warn "you should never see this, because it crashed.\n";