docstr: Even if a NamedTuple is only used as an input argument, saving and
  loading should work correctly.
code: def test_save_namedtuple_input_only(self):
      """
      Even if a NamedTuple is only used as an input argument, saving and
      loading should work correctly.
      """
      global FooTuple  # see [local resolution in python]
  
      class FooTuple(NamedTuple):
          a: int
  
      class MyModule(torch.nn.Module):
          def forward(self, x: FooTuple) -> torch.Tensor:
              return torch.tensor(3)
  
      m_loaded = self.getExportImportCopy(torch.jit.script(MyModule()))
      output = m_loaded(FooTuple(a=5))
      self.assertEqual(output, torch.tensor(3))
  
imports: import io
  import os
  import pathlib
  import sys
  from typing import NamedTuple, Optional
  import torch
  from torch import Tensor
  from torch.testing._internal.common_utils import TemporaryFileName
  from torch.testing._internal.jit_utils import JitTestCase, clear_class_registry
label_desc: Use image node_id 8 for calling the TestSaveLoad obj's underlying member method code with example usage: obj.test_save_namedtuple_input_only() and returns: torch