Sum It Up... Recursively!

Base case: if n is 0 or less, return 0 .
Recursive case: otherwise, return n plus countdown_sum(n - 1) .

Let's revisit adding up numbers from n down to 1 — but this time using recursion, where a function calls itself! 🌀

Finish countdown_sum(n):

💡 need a hint?

func-countdown-recursion.py🔒 given lines are locked — write your code in between