code: def test_get_set_sensor_positions():
      """Test get/set functions for sensor positions."""
      raw1 = read_raw_fif(raw_fname)
      picks = pick_types(raw1.info, meg=False, eeg=True)
      pos = np.array([ch["loc"][:3] for ch in raw1.info["chs"]])[picks]
      raw_pos = raw1._get_channel_positions(picks=picks)
      assert_array_equal(raw_pos, pos)
  
      ch_name = raw1.info["ch_names"][13]
      pytest.raises(
          ValueError, raw1._set_channel_positions, [1, 2], ["name"]
      )
      raw2 = read_raw_fif(raw_fname)
      raw2.info["chs"][13]["loc"][:3] = np.array([1, 2, 3])
      raw1._set_channel_positions([[1, 2, 3]], [ch_name])
      assert_array_equal(
          raw1.info["chs"][13]["loc"], raw2.info["chs"][13]["loc"]
      )
  
imports: import hashlib
  from copy import deepcopy
  from functools import partial
  from pathlib import Path
  import numpy
  import pytest
  from numpy.testing import assert_allclose, assert_array_equal, assert_equal
  from scipy.io import savemat
  from mne import Epochs, EpochsArray, EvokedArray, create_info, make_ad_hoc_cov, pick_channels, pick_types, read_events
  from mne._fiff.constants import FIFF, _ch_unit_mul_named
  from mne.channels import combine_channels, equalize_channels, find_ch_adjacency, get_builtin_ch_adjacencies, make_1020_channel_selections, read_ch_adjacency, read_custom_montage, rename_channels
  from mne.channels.channels import _BUILTIN_CHANNEL_ADJACENCIES, _BuiltinChannelAdjacency, _ch_neighbor_adjacency, _compute_ch_adjacency
  from mne.datasets import testing
  from mne.io import RawArray, read_info, read_raw_bti, read_raw_ctf, read_raw_eeglab, read_raw_fif, read_raw_kit
  from mne.parallel import parallel_func
  from mne.utils import requires_good_network
label_desc: Use image node_id 9 for calling a global function with example usage: test_get_set_sensor_positions() without return types