Lots of very practical tips and tricks for taking your Python programming to the next level. The section on the python AST and Hy was really mind opening. Basically Hy is a Lisp variation that you can use within Python projects, made possible by hacking the Python Abstract Syntax Tree (AST).
Generally the book is a quick read, but full of little things that the author learned by using Python on very large and complex projects. Worth a read because it'll open your eyes to what's possible with Python, in a succinct and elegant way.
Not life changing, but certainly very interesting. Easy 4/5.