utilties.rkt function parses incorrectly when using book.

[pyrofolium]

When I run this:

(require "utilities.rkt")

(define x (parse-program `(program () (+ 10 (- (+ 5 3))))))

(define y
  (Program '() (Prim '+ (list (Int 10) (Prim '- (list (Prim '+ (list (Int 5) (Int 3))))))
  

the values on the repl display different things for y and x. In fact the interp-Rint function in the book actually can't parse x. If users follow the book it doesn't exactly work..?