code: def get_3d_image(self):
      image_shape = (1, 200, 200, 1)
      elements = tf.range(np.prod(image_shape), dtype=tf.float32)
      image = tf.reshape(elements, image_shape)
      return image
  
file_path: NiftyNet/tests/affine_augmentation_test.py
imports: from __future__ import absolute_import, print_function
  import numpy
  import tensorflow
  from niftynet.layer.affine_augmentation import AffineAugmentationLayer
  from tests.niftynet_testcase import NiftyNetTestCase
label_desc: Use image node_id 1 for calling the RandRotationTest obj's underlying member method code with example usage: obj.get_3d_image() and returns: image