[2.7] bpo-32857: Raise error when tkinter after_cancel() is called with None (GH-5701) by csabella · Pull Request #6620 · python/cpython

@serhiy-storchaka I had to change the side effect on the tests because nonlocal was invalid. Modifying a dictionary was suggested on SO, but if that isn't the best solution, then I can change it.

Thank you @csabella!

I usually use a list, but using a dict is a good solution too, and it it may be the best solution in this case.

Finally I have caught the moment when tests are passed and the branch is in sync! 😫