After we talked about memory allocation in Python back in Episode 16, we're ready to complain, uh, explain reference counting. Or at least throw a bunch of reference counting facts at you. Plus a big assortment of recent Python changes. You ready?

## Timestamps

(00:00:00 ) INTRO

(00:04:17 ) PART 0: SPORTS NEWS

(00:06:53 ) PART 1: REFERENCE COUNTING

(00:08:28 ) New segment of 2025

(00:13:54 ) C++ is asymptotic Python

(00:15:37 ) Is Rust game yet?

(00:18:01 ) Names

(00:20:25 ) Breaking the law

(00:23:08 ) sys.getrefcount()

(00:25:21 ) Pedantic Pablo

(00:26:06 ) sys.gettotalrefcount()

(00:31:24 ) TraceRefs

(00:33:28 ) Advantages of refcounting

(00:36:16 ) Disadvantages of refcounting

(00:38:40 ) Reference cycles

(00:40:39 ) Multithreading

(00:41:25 ) When refcounting goes wrong

(00:44:05 ) Freeing memory in Python doesn't return it to the OS

(00:45:42 ) Leaks and cycles redux

(00:50:29 ) Double free

(00:53:05 ) Avoiding reference counting

(00:54:59 ) Immortal objects

(01:00:40 ) PART 2: WHAT'S GOING ON IN CPYTHON

(01:02:43 ) New features

(01:04:11 ) Assorted interesting changes

(01:15:23 ) Performance

(01:18:09 ) Free-threading changes galore

(01:27:02 ) AsyncIO

(01:34:25 ) Windows changes

(01:36:45 ) Security

(01:37:20 ) OUTRO