Fixed

i dont think this is an issue, because the semantics are different: (named) tuples are immutable, while class instances are mutable

Don't know what happened:-( Description modified. Thanks!

Already get it after completing the kata. This is pretty unobvious for those who don't work with typing.

This moment is the most unpleasant in the task (if you control every case by yourself).
Perhaps it is worth describe it further.