code: def testGatherGrad(self):
      x = tf.constant([[1.0, 2.0], [3.0, 4.0], [5.0, 6.0]])
      idx = tf.constant([1, 0, 1, 2])
      out = mp_ops.gather(x, idx)
      with self.test_session():
          diff = tf.test.compute_gradient_error(x, [3, 2], out, [4, 2])
          self.assertLess(diff, 1e-4)
  
file_path: euler/tf_euler/python/euler_ops/mp_ops_test.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import tensorflow
  from tf_euler.python.euler_ops import mp_ops
label_desc: Use image node_id 8 for calling the ScatterTest obj's underlying member method code with example usage: obj.testGatherGrad() without return types