python3 冒泡排序法

    def MySort(self , arr: List[int]) -> List[int]:
        # write code here
        n=len(arr)
        for i in range(0,n):
            for j in range(i+1,n):
                if arr[j]<arr[i]:
                    k=arr[i]
                    arr[i]=arr[j]
                    arr[j]=k
        return arr