code: def test_compute_maxwell_basis(regularize, n, int_order):
      """Test compute_maxwell_basis."""
      raw = read_raw_fif(raw_small_fname).crop(0, 2)
      assert raw.info["bads"] == []
      raw.del_proj()
      rank = compute_rank(raw)["meg"]
      assert rank == 306
      raw.info["bads"] = ["MEG 2443"]
      kwargs = dict(
          regularize=regularize, int_order=int_order, verbose=True
      )
      raw_sss = maxwell_filter(raw, **kwargs)
      want = raw_sss.get_data("meg")
      rank = compute_rank(raw_sss)["meg"]
      assert rank == n
      S, pS, reg_moments, n_use_in = compute_maxwell_basis(
          raw.info, **kwargs
      )
      assert n_use_in == n
      assert n_use_in == len(reg_moments) - 15  # no externals removed
      xform = S[:, :n_use_in] @ pS[:n_use_in]
      got = xform @ raw.pick(picks="meg", exclude="bads").get_data()
      assert_allclose(got, want)
  
imports: import pathlib
  import re
  from contextlib import contextmanager
  from pathlib import Path
  import numpy
  import pytest
  from numpy.testing import assert_allclose, assert_array_equal
  from scipy import sparse
  from scipy.special import sph_harm
  import mne
  from mne import compute_raw_covariance, concatenate_raws, pick_info, pick_types
  from mne._fiff.constants import FIFF
  from mne.annotations import _annotations_starts_stops
  from mne.chpi import filter_chpi, read_head_pos
  from mne.datasets import testing
  from mne.forward import _prep_meg_channels, use_coil_def
  from mne.io import BaseRaw, read_info, read_raw_bti, read_raw_ctf, read_raw_fif, read_raw_kit
  from mne.preprocessing import annotate_amplitude, annotate_movement, compute_maxwell_basis, find_bad_channels_maxwell, maxwell_filter, maxwell_filter_prepare_emptyroom
  from mne.preprocessing.maxwell import _bases_complex_to_real, _bases_real_to_complex, _get_n_moments, _prep_mf_coils, _sh_complex_to_real, _sh_negate, _sh_real_to_complex, _sss_basis_basic, _trans_sss_basis
  from mne.rank import _compute_rank_int, _get_rank_sss, compute_rank
  from mne.utils import _record_warnings, assert_meg_snr, buggy_mkl_svd, catch_logging, object_diff, use_log_level
label_desc: Use image node_id 28 for calling a global function with example usage: test_compute_maxwell_basis(regularize, n, int_order) without return types