code: def test_namespace_difference():
      ns1 = Namespace()
      ns2 = Namespace()
      assert ns1 != ns2
  
imports: import copy
  from torch import nn
  from torch.distributed.pipeline.sync.skip import Namespace, skippable, stash
  from torch.testing._internal.common_utils import run_tests
label_desc: Use image node_id 1 for calling a global function with example usage: test_namespace_difference() without return types