automatic function

[pmcurtin]

#47

[pmcurtin]

@apoorvkh Was this kind of what you were thinking of? The automatic function returns the hostnames and workers_per_host arguments for launch... The user would have to call hosts, workers = automatic() and then manually pass the arguments to launch. We could just add a flag to launch that causes it to call automatic internally and use its output rather than the hostnames and workers that the user passes.

We can also rename automatic to something more descriptive like automatic_topology (idk).

[apoorvkh]

Yeah, close to what I was suggesting! See comments.

And I agree, we should add flags to launch: e.g. launch(..., auto=True, hostnames=None, workers=None) where this would infer if hostnames is None: hostnames = auto_hosts() etc.

[apoorvkh]

LGTM -- feel free to merge once tests pass