(source [0, 0] - [1, 0]
  (sqr_tup_lit [0, 0] - [0, 20]
    (kwd_lit [0, 1] - [0, 7])
    (kwd_lit [0, 8] - [0, 12])
    (kwd_lit [0, 13] - [0, 19])))
