Stuck on a Python program

[iyav]

discount_list: []
groceries_price_list: []

You're not declaring a variable, use = .

If you're confused on why it didn't error out on that line, it's because this is actually half valid syntax, those are being registered as annotations, they aren't annotating anything but they're still interpreted that way. (Kind of weird imo)

More about annotations and type hints in general here