code: def test_batch_call():
      a = Batch(torch.tensor(42))
      b = Batch((torch.tensor(42), torch.tensor(21)))
  
      def f(x):
          return x
  
      def g(x, y):
          return x, y
  
      assert a.call(f).atomic
      assert not b.call(g).atomic
  
file_path: pytorch/test/distributed/pipeline/sync/test_microbatch.py
imports: import pytest
  import torch
  import torch.cuda
  from torch.distributed.pipeline.sync.microbatch import Batch, check, gather, scatter
  from torch.testing._internal.common_utils import run_tests
label_desc: Use image node_id 3 for calling a global function with example usage: test_batch_call() and returns: x, x,  y