In [1]: a = [1,2,3]
In [2]: a.reverse()
In [3]: a
Out[3]: [3, 2, 1]
方法二:
In [9]: a = [1,2,3]
In [10]: for i in reversed(a):
....: print i
....:
3
2
1
In [11]: a = [1,2,3]
In [12]: for i in a[::-1]:
....: print i
....:
3
2
1