code: def test_plot_raw_nan(raw, browser_backend):
      """Test plotting all NaNs."""
      raw._data[:] = np.nan
      # this should (at least) not die, the output should pretty clearly show
      # that there is a problem so probably okay to just plot something blank
      with _record_warnings():
          raw.plot(scalings="auto")
  
imports: import itertools
  import os
  from copy import deepcopy
  import matplotlib.pyplot
  import numpy
  import pytest
  from matplotlib import backend_bases
  from numpy.testing import assert_allclose
  from mne import Annotations, create_info, pick_types
  from mne._fiff.pick import _DATA_CH_TYPES_ORDER_DEFAULT, _PICK_TYPES_DATA_DICT
  from mne.annotations import _sync_onset
  from mne.datasets import testing
  from mne.io import RawArray
  from mne.utils import _assert_no_instances, _dt_to_stamp, _record_warnings, check_version, get_config, set_config
  from mne.viz import plot_raw, plot_sensors
  from mne.viz.utils import _fake_click, _fake_keypress
label_desc: Use image node_id 20 for calling a global function with example usage: test_plot_raw_nan(raw, browser_backend) without return types