<LeetCode><Easy> 191 Number Of 1 Bit

Write a function that takes an unsigned integer and returns the number of ’1' bits it has (also known as the Hamming
weight).

For example, the 32-bit integer ’11' has binary representation 

00000000000000000000000000001011

,
so the function should return 3.

#Python2 48ms

class Solution(object):
def hammingWeight(self, n):
return bin(n)[2:].count('1')