code: def test_operator_natural_logarithm():
      shapes = [(1, 4096), (2, 1000), (2, 3, 40)]
      batch_size = 3
      for device in ["cpu", "gpu"]:
          for sh in shapes:
              yield check_natural_logarithm, device, batch_size, sh
  
imports: from nvidia.dali.pipeline import Pipeline
  import nvidia.dali.ops
  import numpy
  from functools import partial
  from test_utils import compare_pipelines
  from test_utils import RandomDataIterator
  from nose_utils import raises
label_desc: Use image node_id 6 for calling a global function with example usage: test_operator_natural_logarithm() without return types