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This is mostly directed at the Oslo cores, some of whom have already 
been -1'ing these patches (thanks!).

There have been some discussions in the tc channel, but I'm not sure 
we've actually talked about it within the team yet. The main thing is 
that Oslo needs to wait until all of our consumers have stopped testing 
py27 before we do. Otherwise we may accidentally merge a 
py27-incompatible change and break other projects' gate jobs. Some 
patches to drop py27 jobs have already been proposed, and in lieu of 
someone procedural -2'ing all of them I'm hoping we can just have an 
understanding that these can't merge yet.

I'll send a followup when we're ready to proceed with the py27 removal work.

Thanks.

-Ben