code: def testGetNextAsOptional(self):
      dataset = dataset_ops.Dataset.range(10)
      multi_device_iterator = (
          multi_device_iterator_ops.MultiDeviceIterator(
              dataset, [self._devices[1], self._devices[2]]
          )
      )
  
      self.evaluate(multi_device_iterator.initializer)
      for i in range(0, 10, 2):
          (
              elem_on_1,
              elem_on_2,
          ) = multi_device_iterator.get_next_as_optional()
          has_elem_1, get_elem_1 = self.evaluate(
              [elem_on_1.has_value(), elem_on_1.get_value()]
          )
          has_elem_2, get_elem_2 = self.evaluate(
              [elem_on_2.has_value(), elem_on_2.get_value()]
          )
          self.assertTrue(has_elem_1)
          self.assertEqual(i, get_elem_1)
          self.assertTrue(has_elem_2)
          self.assertEqual(i + 1, get_elem_2)
      (
          elem_on_1,
          elem_on_2,
      ) = multi_device_iterator.get_next_as_optional()
      has_elem_1 = elem_on_1.has_value()
      has_elem_2 = elem_on_2.has_value()
      self.assertFalse(self.evaluate(has_elem_1))
      self.assertFalse(self.evaluate(has_elem_2))
      with self.assertRaises(errors.InvalidArgumentError):
          elem_1 = elem_on_1.get_value()
          self.evaluate(elem_1)
      with self.assertRaises(errors.InvalidArgumentError):
          elem_2 = elem_on_2.get_value()
          self.evaluate(elem_2)
  
imports: from absl.testing import parameterized
  import numpy
  from tensorflow.python.data.experimental.ops import testing
  from tensorflow.python.data.kernel_tests import test_base
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.data.ops import from_generator_op
  from tensorflow.python.data.ops import multi_device_iterator_ops
  from tensorflow.python.data.ops import options
  from tensorflow.python.eager import cancellation
  from tensorflow.python.eager import context
  from tensorflow.python.eager import def_function
  from tensorflow.python.eager import executor
  from tensorflow.python.framework import combinations
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import tensor_spec
  from tensorflow.python.ops import data_flow_ops
  from tensorflow.python.platform import test
label_desc: Use image node_id 7 for calling the MultiDeviceIteratorTest obj's underlying member method code with example usage: obj.testGetNextAsOptional() without return types