Complement of Base 10 Integer LeetCode solution in Python

1
class Solution:
2
    def bitwiseComplement(self, n: int) -> int:
3
        cnt = 0
4
        ans = 0
5
        if n == 0:
6
            return 1
7
        while n > 0:
8
            if n & 1:
9
                cnt += 1
10
            else:
11
                ans = ans + (2**cnt)
12
                cnt += 1
13
            n = n >> 1
14
        return ans