code: def testOneDevice(self):
      result = distribute_utils.regroup((_nested_value("1"),))
      # On one device regroup() and select_replica() are basically identity.
      self.assertEqual(_nested_value("1"), result)
      self.assertEqual(
          _nested_value("1"), distribute_utils.select_replica(0, result)
      )
  
imports: import collections
  import collections.abc
  from absl.testing import parameterized
  import wrapt
  from tensorflow.python.distribute import combinations
  from tensorflow.python.distribute import distribute_utils
  from tensorflow.python.distribute import strategy_combinations
  from tensorflow.python.distribute import values
  from tensorflow.python.eager import context
  from tensorflow.python.eager import test
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import variable_scope
  from tensorflow.python.ops import variable_v1
  from tensorflow.python.saved_model.model_utils import mode_keys
label_desc: Use image node_id 9 for calling the RegroupAndSelectDeviceTest obj's underlying member method code with example usage: obj.testOneDevice() without return types