I really wonder why no one mentions the official Python tutorial (http://docs.python.org/tutorial/). That is by far, the most concise and easiest to understand Python tutorial I have ever come across. For those who run after multiple sources and 400 pages books, give the official tutorial a read. You will not even feel at looking at another Python introductory book again. I speak from personal experience and based on the feedback from the people I recommended this -- they simply love it. As talk is cheap, don't listen to me and go ahead and give it the first few pages a read. You won't regret it.