code: def _label_basis(order):
      """Give basis vectors names for Projection() class."""
      return [
          f"HFC: l={L} m={m}"
          for L in np.arange(1, order + 1)
          for m in np.arange(-1 * L, L + 1)
      ]
  
imports: import numpy
  from .._fiff.pick import _picks_to_idx, pick_info
  from .._fiff.proj import Projection
  from ..utils import verbose
  from .maxwell import _prep_mf_coils, _sss_basis
label_desc: Use image node_id 2 for calling a global function with example usage: _label_basis(order) and returns: unknown