The condition statement does not work in a function with return, how to fix it?

Question

Python

The function returns not None only if the numbers already arranged in the correct order are run through it. The task of the function to sort from largest to smallest is completely confused (yes, I understand that this code is one big complication, but it needs to work in this form).

def terra(num):
    exit = len(num) - 1
    for i in range(len(num)-1):
        if num[i] < num[i + 1]:
            b = num[i + 1]
            num.pop(i + 1)
            num.insert(i,b)
        elif num[i] >= num[i + 1]:
            exit = exit - 1
    if exit == 0:
        return num
    else:
        terra(num)

Answer 1

I figured out where I went wrong:

if exit == 0:
    num.pop()
    return num
else:
    return terra(num)