I think we should aspire for this to be the case too, eventually. When this has come up in the past, we’ve said that it’s not appropriate to change PEP 394 until Python 2 is officially deprecated. OTOH, I appreciate that distros and others have to make decisions on this now. I think it’s worth discussing where we eventually want to be as a community, even if we continue to recommend no official change until 2020.
I don't think end-users will see any discontinuity in 2020. For quite a while now, more and more people have shifted from using python2 as the default to using python3 as the default. On the other hand, some folks are still using python2, and will continue to do so after 2020 (old, still supported versions RedHat anyone?) Hopefully, after 2020 no one will start anything new with py2, but it's going to be around for a long, long time.
So as there will be no time for a "clear break", we might as well make changes when the time "seems" right. And has been pointed out in this thread, there are a lot of folks not following the PEP anyway (virtual environments, conda, ??). I myself have been telling my newbie students to make a link from "python" to python3 for a couple years (before I saw that PEP!).
I personally would like for `python` to be the latest Python 3 version (or perhaps Brett’s launcher), `python2` to be Python 2.7 where installed (and not mandatory). `python3` would be an alias for the latest Python 3.
+1
Starting now.
-CHB
Christopher Barker, Ph.D.
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