{"ast_node_type":"other","tokens":[{"end":72,"kind":"keyword","start":0,"text":"assert_eq!(set.get_by_key(3).copied().collect::<Vec<_>>(),"}]}
    assert_eq!(set.get_by_key(3).copied().collect::<Vec<_>>(), vec![0]);
    // `get_by_key` works.
    assert!(set.get_by_key(4).next().is_none());