append列表只能尾部一次添加一个元素嘛?
>>> c.append([50,60])
>>> c
[0, 27, 54, 81, 108, 135, 162, 189, 216, 243, 270, 297, 999, [50, 60]]
>>> c.append(50,60)
Traceback (most recent call last):
File "<pyshell#17>", line 1, in <module>
c.append(50,60)
TypeError: append() takes exactly one argument (2 given)
>>>
当添加两个必须带【】?