MY-TEST> (flet ((pred (x y) (or (< (first x) (first y))
                                (and (= (first x) (first y))
                                     (string< (second x) (second y))))))
           (let ((list '((1 "spade") (2 "heart") (3 "spade") (4 "heart")
                         (12 "heart") (6 "heart") (2 "spade"))))
             (stable-sort (copy-list list) #'pred)))

((1 "spade") (2 "heart") (2 "spade") (3 "spade") (4 "heart") (6 "heart") (12 "heart"))