%classic = (
    TheMagicFlute1791Mozart => {
        title => "The Magic Flute", 
        type => "opera",
        author   => "Mozart",
        year      => "1791",
        #... space for lots and lots of optional fields...
    },
    Armida1783Haydn=> {
        title => "Armida",
        type => "Opera",
        author => "Haydn",
        year => "1783",
        characters => ["Armida","Rinaldo","Zelmira",...], 
        # libretto => FORGET, ADD LATER,
    },
);