code: def world_size(self) -> int:
      return min(torch.cuda.device_count(), 2)
  
imports: import copy
  import typing
  import unittest
  import torch
  import torch.nn
  from torch.testing._internal import common_utils
  from apex.transformer.testing.distributed_test_base import NcclDistributedTestBase
label_desc: Use image node_id 2 for calling the TestCudnnGBN obj's underlying member method code with example usage: obj.world_size() and returns: min