code: def test_plotting_memory_garbage_collection(raw, pg_backend):
      """Test that memory can be garbage collected properly."""
      pytest.importorskip("mne_qt_browser", minversion="0.4")
      raw.plot().close()
      import mne_qt_browser
      from mne_qt_browser._pg_figure import MNEQtBrowser
  
      assert len(mne_qt_browser._browser_instances) == 0
      _assert_no_instances(MNEQtBrowser, "after closing")
  
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 36 for calling a global function with example usage: test_plotting_memory_garbage_collection(raw, pg_backend) without return types