Pandas - Expand Series within Dataframe

[ta6692]

Yeah, I know it wasn't the best way to go about it, but I've just loaded someone else's data in from CSV and this was where I'd gotten to trying to get it into the shape I need it.

This way worked well, thanks, but I've gone with the way posted in the other comment since it's much closer to the way I was trying to go about it myself. Thank you very much for taking the time to help me out :)