code: def testCreateCriticalSectionFnReturnsOp(self):
      cs = critical_section_ops.CriticalSection(shared_name="cs")
      v = resource_variable_ops.ResourceVariable(0.0, name="v")
  
      def fn_return_op(a, b):
          c = v.read_value()
          with ops.control_dependencies([c]):
              nv = v.assign_add(a * b)
              with ops.control_dependencies([nv]):
                  return control_flow_ops.no_op()
  
      num_concurrent = 100
      r = [
          cs.execute(lambda: fn_return_op(1.0, 2.0))
          for _ in range(num_concurrent)
      ]
      self.evaluate(v.initializer)
      self.evaluate(r)
      final_v = self.evaluate(v)
      self.assertAllClose(2.0 * num_concurrent, final_v)
  
imports: import itertools
  from absl.testing import parameterized
  from tensorflow.python.data.experimental.ops import prefetching_ops
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.eager import context
  from tensorflow.python.eager import def_function
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import cond
  from tensorflow.python.ops import control_flow_assert
  from tensorflow.python.ops import control_flow_ops
  from tensorflow.python.ops import control_flow_v2_toggles
  from tensorflow.python.ops import critical_section_ops
  from tensorflow.python.ops import resource_variable_ops
  from tensorflow.python.ops import while_loop
  from tensorflow.python.platform import test
  from tensorflow.python.platform import tf_logging
label_desc: Use image node_id 4 for calling the CriticalSectionTest obj's underlying member method code with example usage: obj.testCreateCriticalSectionFnReturnsOp() and returns: control_flow_ops