See if you know where this leads before clicking on it: https://xkcd.com/208/
Python was designed from the start so that 'foo' and "foo" are equal. It also worked like that for 30 years or so. This has not been an issue in these 30 years. But then someone came with an opinion that one of them is better than the other.
Add a look-behind for '[' and a look-ahead for ']' and you'll be fine.