Missing argument when initializing parallel driver

[chenzizhao]

Hi, the initialization of _env_server seems to have an extra "context" object. At least it was not needed in portal/tests
/test_process.py. Did I miss anything? Is it safe to rid the context argument and replace context.running with True?

dreamerv3/embodied/core/driver.py

Lines 16 to 24 in 55c8c67

	if parallel:
	import multiprocessing as mp
	context = mp.get_context()
	self.pipes, pipes = zip(*[context.Pipe() for _ in range(self.length)])
	fns = [cloudpickle.dumps(fn) for fn in make_env_fns]
	self.procs = [
	portal.Process(self._env_server, i, pipe, fn, start=True)
	for i, (fn, pipe) in enumerate(zip(fns, pipes))]
	self.pipes[0].send(('act_space',))

dreamerv3/embodied/core/driver.py

Lines 101 to 110 in 55c8c67

	@staticmethod
	def _env_server(context, envid, pipe, ctor):
	try:
	ctor = cloudpickle.loads(ctor)
	env = ctor()
	while context.running:
	if not pipe.poll(0.1):
	time.sleep(0.1)
	continue
	try: