Is there anything that is currently blocking this patch? I'd quite like it to get into PG16.
Especially since I ran into another use case that I would want to use this patch for recently: Adding an async cancel function to Python it's psycopg3 library. This library exposes both a Connection class and an AsyncConnection class (using python its asyncio feature). But one downside of the AsyncConnection type is that it doesn't have a cancel method. I ran into this while changing the PgBouncer tests to use python. And the cancellation tests were the only tests that required me to use a ThreadPoolExecutor instead of simply being able to use async-await style programming: https://github.com/pgbouncer/pgbouncer/blob/master/test/test_cancel.py#LL9C17-L9C17
