code: def testGetNextAsOptionalExampleUsage(self, distribution):
      global_batch_size = 2
      steps_per_loop = 6
      dataset = dataset_ops.Dataset.range(
          8, output_type=dtypes.int32
      ).batch(global_batch_size)
      distributed_iterator = iter(
          distribution.experimental_distribute_dataset(dataset)
      )
  
      @def_function.function
      def train_fn(distributed_iterator):
          def step_fn(x):
              return x
  
          for _ in math_ops.range(steps_per_loop):
              optional_data = (
                  distributed_iterator.get_next_as_optional()
              )
              if not optional_data.has_value():
                  break
              distribution.run(
                  step_fn, args=(optional_data.get_value(),)
              )
  
      train_fn(distributed_iterator)
  
imports: from absl.testing import parameterized
  from tensorflow.python import tf2
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.distribute import combinations
  from tensorflow.python.distribute import device_util
  from tensorflow.python.distribute import distribute_lib
  from tensorflow.python.distribute import reduce_util
  from tensorflow.python.distribute import strategy_combinations
  from tensorflow.python.distribute import test_util
  from tensorflow.python.eager import def_function
  from tensorflow.python.eager import test
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import control_flow_assert
  from tensorflow.python.ops import map_fn
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.ops.losses import losses
  from tensorflow.python.tpu import tpu
  from tensorflow.python.util import nest
label_desc: Use image node_id 5 for calling the InputIterationTest obj's underlying member method code with example usage: obj.testGetNextAsOptionalExampleUsage(distribution) and returns: x