[core-workflow] Adding a "requires C" keyword?

[francis]

Hi Nick,

> I'm not particularly enamoured of that specific keyword name, so I'm
> interested in two specific kinds of feedback:
>
> 1. Does the extra keyword sound useful?
Yes, IMHO it's useful



Just complementary info about the context where the new keyword should 
be used is [1] (AFAIK):


buildbot
     A buildbot triggered the issue being reported.

easy
     Fixing the issue should not take longer than a day for someone new 
to contributing to Python to solve.

gsoc
     The issue would fit as, or is related to, a GSoC project.

needs review
     The patch attached to the issue is in need of a review.

patch
     There is a patch attached to the issue.

3.3regression
     The issue is a regression in 3.3.



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[1] https://docs.python.org/devguide/triaging.html


Regards,
francis