code: def test_batch_non_atomic():
      x, y = torch.tensor(42), torch.tensor(21)
      b = Batch((x, y), 0)
  
      assert not b.atomic
  
      with pytest.raises(AttributeError):
          b.tensor
      assert b.tensors == (x, y)
  
      assert list(b) == [x, y]
      assert len(b) == 2
      assert b[0] is x
      assert b[1] is y
  
file_path: fairscale/tests/nn/pipe/test_microbatch.py
imports: import pytest
  import torch
  import torch.cuda
  from fairscale.nn.pipe.microbatch import Batch, check, gather, scatter
label_desc: Use image node_id 2 for calling a global function with example usage: test_batch_non_atomic() without return types