code: def testNestedDefaultMesh(self):
      @polymorphic_function.function
      def func(a):
          return a + 3.0
  
      with api.default_mesh(self.first_mesh):
          with api.default_mesh(self.second_mesh):
              with api.default_mesh(self.first_mesh):
                  result = func(array_ops.ones(shape=()))
                  self.assertEqual(
                      api.fetch_layout(result).mesh, self.first_mesh
                  )
              result = func(array_ops.ones(shape=()))
              self.assertEqual(
                  api.fetch_layout(result).mesh, self.second_mesh
              )
          result = func(array_ops.ones(shape=()))
          self.assertEqual(
              api.fetch_layout(result).mesh, self.first_mesh
          )
  
imports: from absl.testing import parameterized
  import numpy
  from tensorflow.dtensor.python import accelerator_util
  from tensorflow.dtensor.python import api
  from tensorflow.dtensor.python import config
  from tensorflow.dtensor.python import d_variable
  from tensorflow.dtensor.python import layout
  from tensorflow.dtensor.python.tests import test_util
  from tensorflow.python.eager import backprop
  from tensorflow.python.eager import context
  from tensorflow.python.eager.polymorphic_function import polymorphic_function
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors_impl
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import gen_math_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.platform import test
label_desc: Use image node_id 5 for calling the MultiMeshTest obj's underlying member method code with example usage: obj.testNestedDefaultMesh() and returns: unknown