code: def testIsLoopExit(self):
      exit_op = control_flow_ops.exit(1).op
      self.assertTrue(control_flow_util.IsLoopExit(exit_op))
  
      ref_exit = control_flow_ops.exit(test_ops.ref_output()).op
      self.assertTrue(control_flow_util.IsLoopExit(ref_exit))
  
      self.assertFalse(
          control_flow_util.IsLoopExit(test_ops.int_output().op)
      )
  
imports: from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_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_ops
  from tensorflow.python.ops import control_flow_util
  from tensorflow.python.ops import gen_control_flow_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import while_loop
  from tensorflow.python.platform import test
label_desc: Use image node_id 3 for calling the ControlFlowUtilTest obj's underlying member method code with example usage: obj.testIsLoopExit() without return types