There is a problem in python tests:

Traceback (most recent call last):
File "/workspace/default/.venv/lib/python3.11/site-packages/codewars_test/test_framework.py", line 112, in wrapper
func()
File "/workspace/default/tests.py", line 126, in single_test
print_chessboard(chessboard)
^^^^^^^^^^^^^^^^
NameError: name 'print_chessboard' is not defined

Item # 71 in RESULT dictionary is (1,): 9

I think, it should be removed or kata description changed to 1 ≤ s.length
Sorry, can't do it myself, possibly I don't have rights for that

Yes, quite sure.
I had to rewrite my solution which started finding squares from 16, because it failed in returning 9...

The description says:
2 ≤ s.length
and:
leading zeros are not allowed

But random tests (in Python) can generate a test with answer 9, which has one digit.

This solution will NOT work with the long strings.
For example, the values

entered_code = 5000 * '11'

correct_code = 10000 * '1'

will result to False!

Ok, got it, thanks!

It is usually considered as a bad practice for a function to have such side effect as a change of the given argument. We either return the new list or change the given list in place, but not both.

I suppose that
correct_tail('abc', 'bc') should return False,
because the second argument is NOT the same as the last letter of the first argument.
This solution returns True instead.