Browsers use Cascading Style Sheets (CSS) to control the appearance of websites. From borders, fonts, and colors to layout, images, and animations, there are roughly 500 different style properties that can be declared with CSS. These properties are what make the visual diversity of the internet possible for your handheld device, desktop browser, and even your printer. Understanding the myriad style properties is a challenge for any front-end developer, but if you want to start an argument, bring up the question of how CSS selectors (the queries that assign style declarations to HTML elements) should be structured.

Shows nested comprehensions in a way I might actually remember how to write + optimizations

The pyblp package is a Python 3 implementation of the nested fixed point algorithm for BLP demand estimation.