code: def test_batch_of_empty_samples(device):
      @pipeline_def
      def pipeline():
          empty_sample = types.Constant([])
          if device == "gpu":
              empty_sample = empty_sample.gpu()
          return fn.normalize(empty_sample, mean=5, stddev=1)
  
      p = pipeline(batch_size=4, device_id=0, num_threads=4)
      p.build()
      p.run()
  
imports: from nvidia.dali.pipeline import Pipeline
  from nvidia.dali import backend
  import nvidia.dali.ops
  import numpy
  from test_utils import dali_type
  from nvidia.dali import fn, pipeline_def, types
  from nose2.tools import params
label_desc: Use image node_id 22 for calling a global function with example usage: test_batch_of_empty_samples(device) and returns: fn