No worries!
It makes the marker expression more interesting and it does kill the DSL idea.
The pro of sticking with the PEP as-is it that it’s done (short of me updating my proof-of-concept and a couple minor tweaks). All the tool authors have signaled they can and would implement the PEP as an export format, so there seems to be buy-in at this point which is obviously a big plus. It also gives a bit of time to live with the PEP and continue to think about where the gaps are for using as the only lock file format for folks. As the Zen of Python says, “never is often better than right now”, so I could write this idea down in a Deferred section and let it go.
The con of not trying to tackle this now is momentum. I have a bit of energy left on this topic to see if it can be resolved (if people even want me to). If I don’t tackle it now I don’t know if anyone will ever bother, and it does keep coming up. Luckily the file format is versioned so technically it could get resolved at a later date and it wouldn’t break the world. As the Zen of Python says, “Now is better than never” (yes, it can contradict itself).
I have no clue what opinions people have or if @pf_moore as PEP delegate has a preference (and yes, that’s an invitation for people to voice an opinion).