排序算法-插入排序

def insert_sort(arr):
    if len(arr) <= 1:
        return
    for i in range(1, len(arr)):
        j = i
        while j > 0:
            if arr[j] < arr[j - 1]:
                arr[j], arr[j - 1] = arr[j - 1], arr[j]
                j -= 1
            else:
                break