下列代码执行后的输出是？（ ）
mylist= [1, 2, 3, 4, 5] newlist = mylist[1:4] newlist.append(6) print(newlist)
[1, 2, 3, 4, 6]
[1, 2, 3, 6]
[2, 3, 4, 6]
[2, 3, 4, 5, 6]