use MP3::Info;
  
my $file = 'fisch.mp3';
my $tag = get_mp3tag($file) or die "No TAG info";
print "GENRE vorher: $tag->{GENRE}\n";
$tag->{GENRE} = 'Rock';
print "GENRE nachher: $tag->{GENRE}\n";
set_mp3tag($file, $tag);