fn main() {
    let db = notmuch::Database::open(&"/home/gustav/.mail", notmuch::DatabaseMode::ReadOnly).unwrap();
    let query = db.create_query("tag:inbox and tag:unread").unwrap();
    let threads = query.search_threads().unwrap();

    for thread in threads {
        println!("thread {:?}, {:?}", thread.subject(), thread.authors());
    }
}