code: def test_build_train_op_no_op(self):
      with context.graph_mode():
          train_op = (
              ensemble.ComplexityRegularizedEnsembler().build_train_op(
                  *[None] * 7
              )
          )  # arguments unused
          self.assertEqual(train_op.type, tf.no_op().type)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import contextlib
  from absl.testing import parameterized
  from adanet import ensemble
  from adanet import subnetwork
  from adanet import tf_compat
  from adanet.core.summary import Summary
  import mock
  import tensorflow.compat.v2
  from tensorflow.python.eager import context
  from tensorflow.python.framework import test_util
label_desc: Use image node_id 6 for calling the ComplexityRegularizedEnsemblerTest obj's underlying member method code with example usage: obj.test_build_train_op_no_op() without return types