Hash me if you can: let's talk about Python dictionaries!

We all use dictionaries constantly, but most of us treat them as a black box. This talk opens that box. We'll walk through how hash tables actually work and what the 2011 "hash flooding" vulnerability taught us about algorithmic complexity attacks. We'll also check some genuinly weird behavior (hash(-1) == hash(-2)), the birthday paradox, and why your hash seeds are randomized. We'll wrap up with a quick tour of other hash-based structures like Bloom filters and consistent hashing.