列表初始化
>>> empty = []
>>> empty
[]
>>> e1 = list()
>>> e1
[]
>>>a = ['a', 1, 2, [1, 2, 3]]
>>> a.append('cmd')
>>> a
['a', 1, 2, [1, 2, 3], 'cmd']
>>> a.append('aa','bb')
>>> len(a)
6
>>> a.extend(['aa','bb'])
>>> len(a)
8
>>> a
['a', 1, 2, [1, 2, 3], 'cmd', [3, 2, 1], 'aa', 'bb']
>>> a.insert(0,'system')
>>> a
['system', 'a', 1, 2, [1, 2, 3], 'cmd', [3, 2, 1], 'aa', 'bb']
>>>
>>>a.remove('bb')
>>> a
['system', 'a', 1, 2, [1, 2, 3], 'cmd', [3, 2, 1], 'aa']
>>>
>>>del a[1]
>>> a
['system', 1, 2, [1, 2, 3], 'cmd', [3, 2, 1], 'aa']
>>>
>>>a.pop(0)
>>> a
[1, 2, [1, 2, 3], 'cmd', [3, 2, 1], 'aa']
>>>
>>>a[1:3]