（一）Python入门-3序列：04列表-元素删除的3种方式-删除本质是数组元素拷贝

1 >>> a = [100,200,888,300,400]
2       
3 >>> del a[2]
4       
5 >>> a
6       
7 [100, 200, 300, 400]

 1 >>> a = [10,20,30,40,50]
 2       
 3 >>> a.pop()
 4       
 5 50
 6 >>> a
 7       
 8 [10, 20, 30, 40]
 9 >>> a.pop(1)
10       
11 20
12 >>> a
13       
14 [10, 30, 40]

 1 >>> a = [10,20,30,40,50,20,30,40,20,30]
 2       
 3 >>> a.remove(20)
 4       
 5 >>> a
 6       
 7 [10, 30, 40, 50, 20, 30, 40, 20, 30]
 8 >>> a.remove(100)
 9       
10 Traceback (most recent call last):
11   File "<pyshell#215>", line 1, in <module>
12     a.remove(100)
13 ValueError: list.remove(x): x not in list