Python has so many libraries that people often forget to take their time to learn about all the really interesting and useful features that Python offers. The Pydon'ts teach you these core features of Python, with plenty of code examples to show you how these features are used in real code in the real world. Python was not my first programming language, and I remember picking it up as a friend of mine recommended it to me. Now, many years later, I still enjoy writing Python code, whether for work-related reasons or for my own projects. In programming, much like in mathematics – my main area of expertise –, there is a sense of elegance in the code (or proofs) we write. As I learned more and more about programming in general and Python in particular, I developed a sense for what I consider to be elegant Python programs. This is one of the things I intend to share in this book: tips on how to write beautiful Python programs. Of course, the notion of elegance is a subjective one, so it may very well be the case that what I find elegant is not what you find elegant, and that is perfectly fine. In general, neither one of us will be wrong. Tied to my effort of sharing my interpretation of what elegant Python programs look like, I also want you to learn about all the nooks and crannies of the core language. Python is a very, very, rich language, and the more you learn about it, the more well equipped you will be to use it to its full potential. That is why every chapter focuses on exploring a single feature of the core language of Python, which is always accompanied by usage examples of said feature. Some times we will look at how Python’s own Standard Library makes use of that feature, other times I will show some of my own code, and other times I will even come up with random examples.