So easy…
$ python
>>> alpha = “Hello World!”
>>> print alpha
Hello World!
>>> beta = alpha[::-1]
>>> print beta
!dlroW olleH
Works with lists too…
$ python
>>> count = [ 'one', 'two', 'three' ]
>>> countdown = count[::-1]
>>> print countdown
['three', 'two', 'one']
Won’t work with dictionaries but it should work with any hash-able type.