>[success] # slice 切片 ~~~ a = slice(0,3) d = [1,2,3,4,] print(d[a]) 打印结果： [1, 2, 3] ~~~ >[danger] ##### start /stop/step ~~~ a = slice(0,3) print(a.start,a.stop,a.step) 打印结果： 0 3 None ~~~