code: def converts(callback, sample, baseline):
      np.testing.assert_array_equal(callback(sample), baseline)
  
file_path: DALI/dali/test/python/test_external_source_impl_utils.py
imports: from nvidia.dali._utils import external_source_impl
  from nvidia.dali import tensors, pipeline_def
  import nvidia.dali.fn
  from nose.tools import assert_equals
  from nose_utils import raises
  from nose.plugins.attrib import attr
  import numpy
label_desc: Use image node_id 2 for calling a global function with example usage: converts(callback, sample, baseline) without return types