code: def test_date_none(tmp_path):
      """Test that DATE_NONE is used properly."""
      # Regression test for gh-5908
      n_chans = 139
      n_samps = 20
      data = np.random.random_sample((n_chans, n_samps))
      ch_names = [f"E{x}" for x in range(n_chans)]
      ch_types = ["eeg"] * n_chans
      info = create_info(
          ch_names=ch_names, ch_types=ch_types, sfreq=2048
      )
      assert info["meas_date"] is None
      raw = RawArray(data=data, info=info)
      fname = tmp_path / "test-raw.fif"
      raw.save(fname)
      raw_read = read_raw_fif(fname, preload=True)
      assert raw_read.info["meas_date"] is None
  
imports: import sys
  from collections import OrderedDict
  from datetime import datetime, timedelta, timezone
  from itertools import repeat
  from pathlib import Path
  import numpy
  import pytest
  from numpy.testing import assert_allclose, assert_array_almost_equal, assert_array_equal, assert_equal
  from pytest import approx
  import mne
  from mne import Annotations, Epochs, annotations_from_events, count_annotations, create_info, events_from_annotations, read_annotations
  from mne.annotations import _handle_meas_date, _read_annotations_txt_parse_header, _sync_onset
  from mne.datasets import testing
  from mne.io import RawArray, concatenate_raws, read_raw_fif
  from mne.utils import _dt_to_stamp, _raw_annot, _record_warnings, _stamp_to_dt, assert_and_remove_boundary_annot, catch_logging, check_version
label_desc: Use image node_id 35 for calling a global function with example usage: test_date_none(tmp_path) without return types