If you already know any other (good) programming language, then "Essential Python Reference" by David Beazley is the way to go. For starters, if you are wondering, this is how I would do it in X, I wonder how to do this in Python - this book would get you the answer the fastest. There is also a detailed introduction (about 70 pages or so, IIRC) that will get you started as well.
Essential Python Reference
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