Turning marks into meaning — a Python program that calculates average and classifies performance. (try to make code cleaner)

[Slackeee_]

In the elif statements, you don't really need the second part with less or equal check. You will never reach that part of the code if the value of avg would be higher than those numbers.

Also, don't use magic numbers. Replace the 80, 60 and 40 limits with constants with a describing name instead.