style: add empty line

Author: BEMELON

number-of-1-bits/bemelon.py

@@ -15,4 +15,4 @@ def hammingWeight(self, n: int) -> int:
         while n > 0: 
             set_bit_cnt += n & 1
             n >>= 1
-        return set_bit_cnt
+        return set_bit_cnt