Process Context
class torch.distributed.elastic.multiprocessing.api.PContext(name, entrypoint, args, envs, stdouts, stderrs, tee_stdouts, tee_stderrs, error_files)
The base class that standardizes operations over a set of processes
   that are launched via different mechanisms. The name "PContext" is
   intentional to disambiguate with
   "torch.multiprocessing.ProcessContext".
Warning:
 stdouts and stderrs should ALWAYS be a superset of tee_stdouts
 and tee_stderrs (respectively) this is b/c tee is implemented as
 a redirect + tail -f <stdout/stderr.log>

class torch.distributed.elastic.multiprocessing.api.MultiprocessContext(name, entrypoint, args, envs, stdouts, stderrs, tee_stdouts, tee_stderrs, error_files, start_method)
"PContext" holding worker processes invoked as a function.
class torch.distributed.elastic.multiprocessing.api.SubprocessContext(name, entrypoint, args, envs, stdouts, stderrs, tee_stdouts, tee_stderrs, error_files)