They may require things such as plastic cut outs and glass depending if you want to be able to have a window to look into the pc. Some cases are 3D Printed although they have to be joined by screws at the end due to the fact that one whole print can take over a week and then it has to be well doesn't but looks better when sanded.
For count digits, you could just convert it to a String and check the length
Sum digits, convert to string then seperate each character with charAt then convert it to numbers in the return statement.
Average digits you can convert it to a String and then convert them back after taking them apart.
From the code you posted, there is no function call to vendingMachine()
Try at the top of your code:
print ("hello")
vendingMachine()
def vendingMachine():
...
Answer:
Click home tab, click conditional formatting, click new rule, use formula to determine
