my $inlist = 0;
while(<>) {
    chop;
    if ( $inlist ||= /^(\<list\>)(.*)$/ ) {
        print "$1<item>";
        $_=$2;
    }
    $inlist &&= !( /^(.*)(\</list\>)$/
                   and print "$1</item>"
                   and $_=$2 );
    print "$_\n";
}
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