Update README.md

Author: artemiy-rodionov

README.md

@@ -4,7 +4,7 @@ Python history blog articles
 This script take articles from the [.blog](http://python-history.blogspot.com) and generate pdf file.
 
 How to run it
-=============
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 #. Install Python 2.6.x or 2.7.x. Installation steps depends on your operating system.