Thanks for advice. I' m using Python 3.x since few past weeks.

better late than never :)

I' m curious: is there a way to format column names and aliases instead of simply copying and pasting them 5 times?

Big sorry, I found my mistake.

This kata checks only chords in root positions.

Thanks!

Frankly speaking, I don't know how to edit comment as an issue...

Sorry for my former comment (about basic knowledge). This is my first approved kata and I never expected that I have to resolve so many issues about it. That's why I eventually a little lost self-control. Best wishes

Maybe mark this as Issue, so that everybody can see before submitting code that sth is wrong with kata...

In which language you find this bug?

Thanks for translation!

ok, no problem :)

In my opinion, it's basic knowledge from school.

AND, OR, XOR are associative and commutative, so the direction of operations doesn't matter. False "AND" false equals false...