code: def get_25d_reader():
      """
      define the 2.5 d reader
      :return:
      """
      reader = ImageReader(["image"])
      reader.initialise(
          SINGLE_25D_DATA, SINGLE_25D_TASK, single_25d_list
      )
      return reader
  
imports: from __future__ import absolute_import, division, print_function
  import os
  import nibabel
  import tensorflow
  import pandas
  import numpy
  from niftynet.engine.sampler_resize_v2 import ResizeSampler
  from niftynet.engine.windows_aggregator_identity import WindowAsImageAggregator
  from niftynet.io.image_reader import ImageReader
  from niftynet.io.image_sets_partitioner import ImageSetsPartitioner
  from niftynet.layer.discrete_label_normalisation import DiscreteLabelNormalisationLayer
  from niftynet.layer.pad import PadLayer
  from niftynet.utilities.util_common import ParserNamespace
  from tests.niftynet_testcase import NiftyNetTestCase
label_desc: Use image node_id 4 for calling a global function with example usage: get_25d_reader() and returns: reader