Re: Time to drop plpython2?

... btw, there's a fairly critical gating factor for any plan to drop
python2 support: the buildfarm. I just counted, and there are exactly
as many members running python 2.x as 3.x (49 apiece), not counting
Windows machines that aren't running configure. We can't commit
something that's going to make half the buildfarm go red.

(It's likely that some fraction of them do already have python3 installed,
in which case the search order change Peter recommended would be enough to
fix it. But I'm sure not all do.)

This ties into the business about converting the build system to meson,
as that also requires python 3 --- with, IIUC, a higher minimum version
than we might otherwise need. I'm disinclined to cause two separate
flag days for buildfarm owners, so what I now think is we ought to put
this idea on the shelf until we've finished that conversion or decided
we're not gonna do it. We need to identify exactly what needs to be
installed before we start pestering the owners.

regards, tom lane