Why when I run this code I'm getting [101, 0, 0], but not [100, 0, 0]?

l = [9, 9]

def add_one(l):
    i = 0
    while i != len(l): #2
        i += 1
        if l[-i] != 9:
            l[-i] += 1
            break
        else:
            l[-i] = 0
            if i == len(l):
                l.insert(-i, 100)
                print(i, "insert")
    return l

add_one(l) You should write your response with 900 or more words.
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