code: def _transform_orig_meg_coils(coils, t, do_es=True):
      """Transform original (device) MEG coil positions."""
      if t is None:
          return
      for coil in coils:
          coil_trans = np.dot(t["trans"], coil["coil_trans_orig"])
          coil.update(
              coord_frame=t["to"],
              r0=coil_trans[:3, 3],
              rmag=apply_trans(coil_trans, coil["rmag_orig"]),
              cosmag=apply_trans(
                  coil_trans, coil["cosmag_orig"], False
              ),
          )
          if do_es:
              r0_exey = (
                  np.dot(coil["rmag_orig"][:, :2], coil_trans[:3, :2].T)
                  + coil_trans[:3, 3]
              )
              coil.update(
                  ex=coil_trans[:3, 0],
                  ey=coil_trans[:3, 1],
                  ez=coil_trans[:3, 2],
                  r0_exey=r0_exey,
              )
  
imports: import os
  import os.path
  from contextlib import contextmanager
  from copy import deepcopy
  from pathlib import Path
  import numpy
  from .._fiff.compensator import get_current_comp, make_compensator
  from .._fiff.constants import FIFF, FWD
  from .._fiff.meas_info import Info, read_info
  from .._fiff.pick import _has_kit_refs, pick_info, pick_types
  from .._fiff.tag import _loc_to_coil_trans, _loc_to_eeg_loc
  from ..bem import ConductorModel, _bem_find_surface, read_bem_solution
  from ..source_estimate import VolSourceEstimate
  from ..source_space._source_space import _complete_vol_src, _ensure_src, _filter_source_spaces, _make_discrete_source_space
  from ..surface import _CheckInside, _normalize_vectors
  from ..transforms import Transform, _coord_frame_name, _ensure_trans, _get_trans, _print_coord_trans, apply_trans, invert_transform, transform_surface_to
  from ..utils import _check_fname, _pl, _validate_type, logger, verbose, warn
  from ._compute_forward import _compute_forwards
  from .forward import _FWD_ORDER, Forward, _merge_fwds, convert_forward_solution
label_desc: Use image node_id 6 for calling a global function with example usage: _transform_orig_meg_coils(coils, t, do_es) without return types