Good news, everyone: there is a nice, creative-commons licensed ( cc-by-nc ) book about python, even with a python3 version:
Think Python: http://www.greenteapress.com/thinkpython/. From the author of “How to think like a computer scientist”, Allen B. Downey. He initially wrote an (also free licensed) java book to improve the learning experience of his students, and a teacher made a python version out of it. The author has all source code examples linked on the book homepage and has a section in the book listing every single contributor who corrected an error or found a typo.
The Think Python book can be ordered directly via Amazon or downloaded as pdf for free.
Other Free Books by Allen Downey are available from Green Tea Press. The book has it's own Facebook page.
As soon as i have worked throug the complete book i will update this review. What i have seen so far was very impressive.
Sadly, the author has no flattr button on his page. But i have one
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