The promise made in the title of this book is not kept. I believe the author needed at least five more years of seasoning, writing Python code probably in the context of contributions to open source projects, before embarking on the project of writing a book about Python for beginning programmers.
This book is obviously not intended for programmers experienced with other languages: the subject matter is far too basic and rudimentary for that.
This book utterly fails to deliver on the promise of learning anything well. It barely scratches the surface of programming, let alone features and idioms of Python programming. It gets nowhere near giving a proper introduction to software design.
In fact, this book explicitly states, about halfway through, that it will not teach the concept of classes in object-oriented programming, and it does not teach anything about object-oriented programming at all. This is a pretty strange state of affairs, given the fact that one can hardly be considered to have the skills necessary to write solid code in Python without knowing something about class-based object oriented programming. It's doubtful that one can even really write solid Python code in a functional programming style without understanding something about object-oriented programming in Python.
This book fails to provide some critical basics of Python, and utterly fails to teach anything about how best to make use of Python's features to write good software. It is not even sufficient to give an experienced programmer from another language a grasp of some basic quirks of the language before jumping into a Python project.
The good points in this book are pretty simple:
1. The appendices about various features of Python, while rudimentary and very sparse, might still be of some use to a complete beginner in concert with an actually halfway decent book about beginning programming in Python. If you can get it for under a buck, and you do not have access to some better reference material (such as in appendices of that hypothetical halfway decent book about beginning programming in Python), maybe this book is worth it for that purpose, but you probably shouldn't bother wasting your (infinitely more valuable) time reading the main instructional materials of the book.
2. While the execution of the project materials in the book is so clumsily presented as to be almost completely useless, there is merit in the basic concept of how it was organized: give a description of what the student of Python should do for the project, in a progressive fashion, in one (segmented) complete explanation from beginning to end, with annotated suggested implementation for the reader to examine when stuck or from which to learn after the fact. Unfortunately, the project is described and designed badly, in the opposite of ideal order, with no useful annotations in the example implementation provided afterward, destroying much of the value of the project.
If there was some way to warn people away from this book -- which may do more harm than good for a new programmer trying to learn Python, teaching bad habits and leaving huge gaps in the reader's knowledge that could prove quite problematic later -- without deprecating the author, I would like to have known it. Unfortunately, I think it's important enough to warn people away from this book that, lacking any better way to do it, I just decided to give it to you straight. Here it is: If you're looking for a book from which you can start learning Python, you should avoid Learn Python in One Day and Learn it Well. It is a book whose title may be interesting advice but bears roughly zero relevance to its contents.