气泡搜索交换（x，y）；

list = [2, 1]if list[0] > list[1]:  list[0], list[1] = list[1], list[0]

def bubble_sort (array: list) -> list:  for i in range(0, len(array) - 1):    for j in range(0, len(array) - 1 - i):      if array[j] > array[j + 1]:        array[j], array[j+1] = array[j+1], array[j]  return arr