Yup. If you wanted to join with spaces then ' '.join(x), if you want to join with commas then ','.join(x), and if you just want a string with everything smashed together then ''.join(x). You get the idea :)

So, ' '.join(x) where x is the name of the list.

Try str.join()

You're not taking into account 3x3 squares. Check the description.

Get a pen & papper and write out the test cases and try and develop your intuition. Is there a scenario where if one of the variables has a certain property the answer is one thing and if not another? etc.

If you return in both if and else inside a loop, your loop will run only once.

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