code: def test_using_pg_from_another_thread(self):
      def stuff_in_other_thread(pg):
          x = torch.rand(4, requires_grad=True)
          dist.all_reduce(x, group=pg)
  
      t = threading.Thread(
          target=stuff_in_other_thread, args=(dist.group.WORLD,)
      )
      t.start()
      t.join()
  
imports: import os
  import sys
  import torch
  import torch.distributed
  from torch._C._distributed_c10d import ReduceOp
  from unittest import skip, SkipTest
  import operator
  from functools import reduce
  import threading
  import torch.autograd
  from torch.testing._internal.common_distributed import spawn_threads_and_init_comms, MultiThreadedTestCase, skip_if_lt_x_gpu
  from torch.testing._internal.common_utils import TestCase, run_tests, IS_SANDCASTLE
label_desc: Use image node_id 14 for calling the TestCollectivesWithBaseClass obj's underlying member method code with example usage: obj.test_using_pg_from_another_thread() without return types