This is a problem with python and functions.

Problem 4-upc.py: UPC validation [25 points] UPC-A codes are used on packaging to identify products; when you go to the grocery, the barcode scanned by the cashier is, typically, a UPC-A code. These codes consist of twelve digits, the first eleven of which are the product code, and the last is a check digit, which must satisfy the following equation: where "did2 djd4dsds dydsdodiod 1d12" are the 12 digits of the code (from left to right). It can be shown that the check digit is sufficient to catch and correct and single-digit error (e.g., mis-reading by barcode scanner). Write a function is upc valid) that accepts an integer argument representing a possible UPC-A code, and argument is non-negative and does not exceed 12 digits (in decimal). Hint: See hint in previous problem about iterating over the digits of an integer. Practice goal: Further practice with accumulation loops. Very similar checksumming methods are frequently used e.g., for ISBNs, credit cards (Luhn's algorithm), etc