code: def world_size(self):
      return WORLD_SIZE
  
imports: import os
  import sys
  from functools import wraps, partial
  import torch
  import torch.distributed
  from torch.testing._internal.common_distributed import MultiProcessTestCase, TEST_SKIPS
  from torch.testing._internal.common_utils import run_tests, TEST_WITH_DEV_DBG_ASAN
label_desc: Use image node_id 3 for calling the TestObjectCollectives obj's underlying member method code with example usage: obj.world_size() and returns: WORLD_SIZE