I'm more curious than anything else for my own sake to know things people might ask. But its interesting how extremely simple things can be complicated if you haven't done them before. Like if someone asks about a relatively simple regex example in python it'd be easy to get if you just were working on a regex but you could get tripped up if it had been a while since working on one. You could say the same thing about working with datetimes. At least this is the type of thing that throws me off in an interview, maybe I'm not a great candidate though.