code: def test_2d_flip_layer(self):
      a = np.array([[0, 1], [2, 3]])
      flip_layer = RandomFlipLayer(flip_axes=[0], flip_probability=1)
      flip_layer.randomise(spatial_rank=2)
      transformed_a = flip_layer(a)
      with self.cached_session() as sess:
          self.assertTrue(
              np.array_equal(transformed_a, np.array([[2, 3], [0, 1]]))
          )
  
file_path: NiftyNet/tests/rand_flip_test.py
imports: from __future__ import absolute_import, print_function
  import os
  import numpy
  import tensorflow
  from niftynet.layer.rand_flip import RandomFlipLayer
  from tests.niftynet_testcase import NiftyNetTestCase
label_desc: Use image node_id 5 for calling the RandFlipTest obj's underlying member method code with example usage: obj.test_2d_flip_layer() without return types