Add Python37 to v802 branch

[pierreluctg]

Hi @drebbe-intrepid, can you port d07203c to the v802 branch?

[drebbe-intrepid]

Yes, I'm not really happy with that commit. I'll try to get it ported here soon. I was waiting for an actual release and not an RC to continue with this.

[drebbe-intrepid]

Support was added in 2.15 and uploaded.