Upgrading to TensorFlow v2 or PyTorch

[fedarko]

As I understand it, either of these will take a decent amount of work (from talking with @gwarmstrong last week it sounds like moving to TF 2 would be less work).

I'm creating this issue mostly so we can keep track of progress on this, in case we want to actually move forward with either of these upgrades. I think TF 1 will stop being officially supported in a year or something, but I forget where I read that so take it with a grain of salt.

For reference: https://www.tensorflow.org/guide/migrate, https://www.tensorflow.org/probability/api_docs/python/tfp/distributions/Multinomial

[mortonjt]

Thanks for raising this issue.

That being said, I'm going to put a strong veto on migrating to TF2. Development time between TF2 and Pytorch is the difference between night and day.

[fedarko]

OK -- I'll defer to you on that front. In any case we don't have to make a decision now, just later on down the line when this becomes more of an urgent problem.