code: def test_missing_res4(tmp_path):
      """Test that res4 missing is handled gracefully."""
      use_ds = tmp_path / ctf_fname_continuous
      shutil.copytree(
          ctf_dir / ctf_fname_continuous,
          tmp_path / ctf_fname_continuous,
      )
      read_raw_ctf(use_ds)
      os.remove(use_ds / (ctf_fname_continuous[:-2] + "meg4"))
      with pytest.raises(OSError, match="could not find the following"):
          read_raw_ctf(use_ds)
  
imports: import copy
  import os
  import shutil
  from datetime import datetime, timezone
  from os import path
  import numpy
  import pytest
  from numpy import array_equal
  from numpy.testing import assert_allclose, assert_array_equal
  import mne
  import mne.io.ctf.info
  from mne import create_info, events_from_annotations, make_forward_solution, pick_types, read_annotations
  from mne._fiff.compensator import get_current_comp
  from mne._fiff.constants import FIFF
  from mne._fiff.pick import _picks_to_idx
  from mne.datasets import brainstorm, spm_face, testing
  from mne.io import RawArray, read_raw_ctf, read_raw_fif
  from mne.io.ctf.constants import CTF
  from mne.io.ctf.info import _convert_time
  from mne.io.tests.test_raw import _test_raw_reader
  from mne.tests.test_annotations import _assert_annotations_equal
  from mne.transforms import apply_trans
  from mne.utils import _clean_names, _record_warnings, _stamp_to_dt, catch_logging
label_desc: Use image node_id 9 for calling a global function with example usage: test_missing_res4(tmp_path) without return types