parallel-letter-frequency example solution fails online

[keiravillekode]

When submitting the example solution online we have the Unicode letters test failing

Code Run
(let ((expected (make-hash-table :test 'equal)))
    (puthash ?ø 1 expected)
    (puthash ?φ 1 expected)
    (puthash ?ほ 1 expected)
    (puthash ?本 1 expected)
    (should (hash-table-contains expected (calculate-frequencies '("ø" "φ" "ほ" "本")))))
Test Failure
(ert-test-failed
     ((should (hash-table-contains expected (calculate-frequencies ...)))
      :form
      (hash-table-contains
       #s(hash-table test equal data (248 1 966 1 12411 1 26412 1))
       #s(hash-table test equal data (227 1 230 1 195 1 207 1)))
      :value nil))

[keiravillekode]

Similarly, when I use bin/test-examples

Ran 13 tests, 4 results as expected, 9 unexpected

9 unexpected results:
   FAILED  combination-of-lower-and-uppercase-letters-punctuation-and-white-space
   FAILED  ignore-letter-casing
   FAILED  large-texts
   FAILED  many-small-texts
   FAILED  one-text-with-multiple-letters
   FAILED  one-text-with-one-letter
   FAILED  two-texts-with-multiple-letters
   FAILED  two-texts-with-one-letter
   FAILED  unicode-letters