code: def _reload_backend(backend_name):
      global backend
      backend = importlib.import_module(
          name=_backend_name_map[backend_name],
          package="mne.viz.backends",
      )
      logger.info("Using %s 3d backend.\n" % backend_name)
  
imports: import importlib
  import time
  from contextlib import contextmanager
  from functools import partial
  import numpy
  from ...utils import _auto_weakref, _check_option, _validate_type, fill_doc, get_config, logger, verbose
  from .._3d import _get_3d_option
  from ..utils import safe_event
  from ._utils import VALID_3D_BACKENDS
label_desc: Use image node_id 1 for calling a global function with example usage: _reload_backend(backend_name) without return types