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From: Uncle Ben <ben@greenba.com>
Newsgroups: comp.lang.python
Subject: mystery string code - help!
Date: Wed, 20 Apr 2011 09:48:30 -0700 (PDT)
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I found this in one of the online cookbooks:

#Raghunath Reddy Peesari 6 years, 3 months ago  # | flag
#There is more simple way. ###

a = 'abcdefghi'
a = a[::-1]

print a

>>> 'ihgfedcba'

As a newbie Pythoner, I understand [] -1]
but would some tell me how '::' does its magic?

Uncle Ben