code: def bricon_ref_pipe(
      data_iterator, contrast_center, dtype, has_3_dims=False
  ):
      brightness, brightness_shift = brightness_params()
      contrast = contrast_param()
      if contrast_center is None:
          contrast_center = contrast_center_param()
      inp = fn.external_source(source=data_iterator)
      layout = "FHWC" if has_3_dims else "HWC"
      return python_function(
          inp,
          brightness,
          brightness_shift,
          contrast,
          contrast_center,
          dali_type_to_np(dtype),
          function=bricon_ref,
          output_layouts=layout,
      )
  
imports: import nvidia.dali.fn
  from nvidia.dali import pipeline_def
  import nvidia.dali.types
  import numpy
  from test_utils import compare_pipelines, python_function
  from test_utils import RandomDataIterator
  from sequences_test_utils import ArgCb, video_suite_helper
  import random
label_desc: Use image node_id 12 for calling a global function with example usage: bricon_ref_pipe(data_iterator, contrast_center, dtype, has_3_dims) and returns: python_function