Using lambda functions to sum digits and count digits

Question

How can I convert these two functions to use lambda notation?

def sum_digits(number):
    if number == 0:
        return 0
    else:
        return (number % 10) + sum_digits(number / 10)

def count_digit(number):
    if number == 0:
        return 0
    else:
        return 1 + count_digit(number/10)

Answer 1

sum_digits = lambda number: 0 if number == 0 else (number % 10) + sum_digits (number / 10)

count_digit = lambda number: 0 if number == 0 else 1 + count_digit(number/10)

Incidentally, this is a bad time to use lambdas, since you need the function names in order for them to call themselves. The point of lambdas is that they're anonymous.