Dive Into Python
According to Textbook Revolution, a student-run site “dedicated to increasing the use of free educational materials by teachers and professors,” A free computer book in a multitude of formats. Bravo!" From the website: "Dive Into Python is a Python book for experienced programmers. You can buy a printed copy, read it online, or download it in a variety of formats. It is also available in multiple languages. Note: Languages include Italian, French, Spanish, Chinese, Korean, and Russian."