code: def test_save_device_pt(device):
      """
      Unit test for _save_device.
      """
      result = save_device(device)
      assert result in {"gpu", "cuda", "cpu"}
  
file_path: alibi-detect/alibi_detect/saving/_pytorch/tests/test_saving_pt.py
imports: from pytest_cases import param_fixture, parametrize, parametrize_with_cases
  from alibi_detect.saving.tests.datasets import ContinuousData
  from alibi_detect.saving.tests.models import encoder_model
  from alibi_detect.cd.pytorch import HiddenOutput
  from alibi_detect.saving.loading import _load_model_config, _load_optimizer_config
  from alibi_detect.saving.saving import _path2str, _save_model_config
  from alibi_detect.saving._pytorch.saving import save_device
  from alibi_detect.saving.schemas import ModelConfig
  import torch
label_desc: Use image node_id 3 for calling a global function with example usage: test_save_device_pt(device) without return types