Ever wonder how companies like New Relic, Data Dog, and Sentry instrument your code? In this talk we will briefly review how to hook into the Python import system in order to instrument code. We'll present some useful design patterns and tricks of the trade. Then, we'll launch straight into real world examples and challenging instrumentation we've done over the years. Take a deep dive with us into some of the most popular Python libraries in use today and learn how they work underneath. We'll talk about proxies, wrapt, async, Python's web server specifications, and more! You will walk away from this talk with an understanding of how instrumentation works under the hood and how to make your own code instrumentation friendly. You'll also learn about various design patterns; some that are gotos for instrumentation and some that make instrumentation nightmarishly difficult. We hope you will join us on this instrumentation journey and come away with an understanding of how it all works to make developer's lives easier.