Thank you so much for this brainstorming kata. Through pain and suffering finally got it. It was a good experience for me.

Is it possible to implement this without using a for loop in other for loop.

Oh, thanks. I will try to optimize code.
And... I'm sorry. I am new to the codewars. Just would like to know.
You can see my unpublished code for this task, right?

All I do is just sequentially look for pieces. But still my code is too slow. Can you inspirate me by any ideas?

Ok

I have got a fail on the test case:

[] None

I have returned False, but received message about failing:

False should equal True

I don’t quite understand why it is should equal True.