use strict;use warnings;
use XML::Twig;

my $t=XML::Twig->new(
    twig_roots => {
        '/root/dict[@key="data"]/list/dict' =>  sub {
            my ($twig,$elt)=@_;
            printf "%s = %s\n", $elt->att("key"), $elt->first_child_text;
        },
    },
)->parsefile('your.xml');