async function main() {
    let library = new BasicLibrary();
    library.register_entity(FileEntity);
    library.register_entity(AudioEntity);
    library.register_entity(SongEntity);

    let file_entity = await library.add(new LocalFile('/run/media/horn/3tb/Music/Nasonov_-_Istoria_avangardnoi_muzyki_-_Pier_Bulez.mp3'));
    let audio_entity = await library.add(new Audio(file_entity.content));
    let song_entity = await library.add(new Song([audio_entity.content]));

    console.log(song_entity)
}