Update 1356.根据数字二进制下1的数目排序.md

新增python代码

problems/1356.根据数字二进制下1的数目排序.md

@@ -156,6 +156,17 @@ class Solution {
 ## Python
 
 ```python
+class Solution:
+    def sortByBits(self, arr: List[int]) -> List[int]:
+        arr.sort(key=lambda num: (self.count_bits(num), num))
+        return arr
+
+    def count_bits(self, num: int) -> int:
+        count = 0
+        while num:
+            num &= num - 1
+            count += 1
+        return count
 ```
 
 ## Go