z-palindromes

I can't pass 12. test case and I can't find case where my solution gives wrong answer. Does anyone know what's so special in test case 12 ?

The test 12 is: it starts with an empty space, and then there are a few hundreds words formed of 3-6 letters which they all are palindromes, and at the end there are two small words that aren't palindromes.
I hope I helped.

Yes, you helped. Thank you very much.