python 的extend 和append 区别

直接上代码：

>>> a=[1,2,3]
>>> b=[4,5,6]
>>> a.extend(b)
>>> a
[1, 2, 3, 4, 5, 6]
>>> a=[1,2,3]
>>> a.append(b)
>>> a
[1, 2, 3, [4, 5, 6]]
>>>