Merge pull request #1576 from eclutsk/master

Added 'Intermediate Python' to Python section in free-programming-boo…

free-programming-books.md

@@ -1549,6 +1549,7 @@ See also [TeX](#tex)
 * [Hitchhiker's Guide to Python!](http://docs.python-guide.org/en/latest/) (2.6)
 * [How to Think Like a Computer Scientist: Learning with Python](http://www.greenteapress.com/thinkpython/thinkCSpy/) - Allen B. Downey, Jeff Elkner and Chris Meyers (2.4)
     * [How to Think Like a Computer Scientist: Learning with Python, Interactive Edition](http://interactivepython.org/courselib/static/thinkcspy/index.html) (3.2)
+* [Intermediate Python](http://book.pythontips.com/en/latest/index.html#) - Muhammad Yasoob Ullah Khalid (1st edition)
 * [Introduction to Programming Using Python](http://python-ebook.blogspot.com) - Cody Jackson (1st edition) (2.3)
 * [Introduction to Programming with Python](http://opentechschool.github.io/python-beginners/en/) (3.3)
 * [Introduction to python](http://kracekumar.com/post/71171551647/introduction-to-python) - Kracekumar (2.7.3)