Switching default python to 3.6?

[Thomas Klausner <tk%giga.or.at@localhost>]

Hi!

Currently, pkgsrc defaults to python 2.7. The newest python is 3.6.

Locally, I've been using pkgsrc with a default of python-3.x for a
long time now, and I don't see any breakage because of that. Packages
that only support python-2.7 still install that version.

I'd like to switch the default to 3.6. Are there any particular
reasons I shouldn't?
 Thomas