In case of 'KokushiMusou', divider just return empty list. So 'fu' can't be calculated. So errors are printed when I run the first example in main page of this repo with 'Kokushi Musou Juusanmen Matchi'.
You don't have fu for kokushi hand (it is irregular hand) and because of that fu_details is None in hand results. You can check it on your side with simple if hand_result.fu_details.
In case of 'KokushiMusou', divider just return empty list. So 'fu' can't be calculated. So errors are printed when I run the first example in main page of this repo with 'Kokushi Musou Juusanmen Matchi'.