how can I improve this python script?
<p><a href="http://dpaste.com/hold/290121/" rel="nofollow">Backup Script</a></p>

<p>Please check the link above, I wrote this small script in python. It backup files from one directory to the other depends upon the user input. I want to know what are the limitations of this script and all the improvements that can be done to it. So that I can learn from my mistakes, I am total beginner to programming and python. Thanks</p>
