Implementation of Luhn Formula

Question

I was trying to implement the Luhn Formula in Python. Here is my code:

import sys


def luhn_check(number):
    if number.isdigit():
        last_digit = int(         


        

Answer 1

I'd keep it simple and easy to read, something like this:

def luhn(value):
    digits = list(map(int,str(value))
    oddSum = sum(digits[-1::-2])
    evnSum = sum([sum(divmod(2 * d, 10)) for d in digits[-2::-2]])
    return (oddSum + evnSum) % 10 == 0

But there's tons of ways to do the same thing. Obviously, you'd have to do it differently to see the actual output, this just sums up the total to determine if the value is valid.

Best!