1
class Solution:
2
    def sortByBits(self, arr: List[int]) -> List[int]:
3
        binary = []
4
        final = []
5
        arr.sort()
6
        for i in arr:
7
            binary.append(bin(i).count("1"))
8
        for i, j in zip(arr, binary):
9
            final.append((i, j))
10
        z = sorted(final, key=lambda x: x[1])
11

12
        ls = []
13
        for k in z:
14
            ls.append(k[0])
15

16
        return ls