[zero3] new API docs?

[stas00]

Would it be possible to document the new API?

I found:

deepspeed.zero_optimization()

which I think tells me if zero is enabled or not.

deepspeed.zero_optimization_stage()

is what I really needed to know to write conditional code for zero2 vs zero3.

Fished those out from dir(deepspeed) ;)

If there is no time to do full docs, at least having a full list of what is considered a public API would be a great start.

I see most of them are sort of properties of the config object, so I'm not sure how safe these are to use in user code.

Thank you!