It is with pleasure that I am formally accepting PEP 621. Thanks to @brettcannon and the other authors for their work in developing the PEP, and to the “cast of thousands” who contributed to the discussions.
After reflection, I have decided that the PEP is initially accepted as provisional, to allow time for any issues identified as tools implement the spec to be ironed out. But I am strictly limiting the provisional status to a maximum of (just over) three months, so the PEP will be declared final on 1st March 2021. If we have fully working implementations of the PEP sooner than that, I’m happy to move the status to final before the deadline.