docstr: Tests that the merge function merges as expected.
docstr_tok: ["Tests","that","the","merge","function","merges","as","expected","."]
code: def test_merge_preset(self, image, image_high, image_low):
      """Tests that the merge function merges as expected."""
      image = tf.expand_dims(tf.expand_dims(image, axis=-1), axis=0)
      image_high = tf.expand_dims(
          tf.expand_dims(image_high, axis=-1), axis=0
      )
      image_low = tf.expand_dims(
          tf.expand_dims(image_low, axis=-1), axis=0
      )
  
      self.assertAllClose(image, pyramid.merge((image_high, image_low)))
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  import numpy
  from six.moves import range
  import tensorflow
  from tensorflow_graphics.image import pyramid
  from tensorflow_graphics.util import test_case
label_desc: Use image node_id 11 for calling the PyramidTest obj's underlying member method code with example usage: obj.test_merge_preset(image, image_high, image_low) without return types