code: def _build_iterator_saver_hook(self, est):
      return iterator_ops.CheckpointInputPipelineHook(est)
  
imports: from absl.testing import parameterized
  from tensorflow.python.checkpoint import checkpoint_management
  from tensorflow.python.data.experimental.ops import iterator_ops
  from tensorflow.python.data.kernel_tests import test_base
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.estimator import estimator_lib
  from tensorflow.python.framework import combinations
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import control_flow_ops
  from tensorflow.python.ops import variable_v1
  from tensorflow.python.platform import test
  from tensorflow.python.training import saver
  from tensorflow.python.training import training_util
label_desc: Use image node_id 3 for calling the CheckpointInputPipelineHookTest obj's underlying member method code with example usage: obj._build_iterator_saver_hook(est) and returns: iterator_ops