[$] "Structural pattern matching" for Python, part 2

We left the saga of PEP 622("Structural Pattern Matching") at the end of June, but thediscussion of a Python "match" statement-superficially similar to a Cswitch but with extra data-matching features-continued. At thispoint, the next steps are up to the Python steeringcouncil, which will determine the fate of the PEP. But there is lotsof discussion to catch up on from the last two months or so.