code: def _get_extra_data_path(home_dir=None):
      """Get path to extra data (config, tables, etc.)."""
      global _temp_home_dir
      if home_dir is None:
          home_dir = os.environ.get("_MNE_FAKE_HOME_DIR")
      if home_dir is None:
          # this has been checked on OSX64, Linux64, and Win32
          if "nt" == os.name.lower():
              APPDATA_DIR = os.getenv("APPDATA")
              USERPROFILE_DIR = os.getenv("USERPROFILE")
              if APPDATA_DIR is not None and op.isdir(
                  op.join(APPDATA_DIR, ".mne")
              ):  # backward-compat
                  home_dir = APPDATA_DIR
              elif USERPROFILE_DIR is not None:
                  home_dir = USERPROFILE_DIR
              else:
                  raise FileNotFoundError(
                      "The USERPROFILE environment variable is not set, cannot "
                      "determine the location of the MNE-Python configuration "
                      "folder"
                  )
              del APPDATA_DIR, USERPROFILE_DIR
          else:
              # This is a more robust way of getting the user's home folder on
              # Linux platforms (not sure about OSX, Unix or BSD) than checking
              # the HOME environment variable. If the user is running some sort
              # of script that isn't launched via the command line (e.g. a script
              # launched via Upstart) then the HOME environment variable will
              # not be set.
              if os.getenv("MNE_DONTWRITE_HOME", "") == "true":
                  if _temp_home_dir is None:
                      _temp_home_dir = tempfile.mkdtemp()
                      atexit.register(
                          partial(
                              shutil.rmtree,
                              _temp_home_dir,
                              ignore_errors=True,
                          )
                      )
                  home_dir = _temp_home_dir
              else:
                  home_dir = os.path.expanduser("~")
  
          if home_dir is None:
              raise ValueError(
                  "mne-python config file path could "
                  "not be determined, please report this "
                  "error to mne-python developers"
              )
  
      return op.join(home_dir, ".mne")
  
imports: import atexit
  import json
  import multiprocessing
  import os
  import os.path
  import platform
  import shutil
  import subprocess
  import sys
  import tempfile
  from functools import lru_cache, partial
  from importlib import import_module
  from pathlib import Path
  from urllib.error import URLError
  from urllib.request import urlopen
  from packaging.version import parse
  from ._logging import logger, warn
  from .check import _check_fname, _check_option, _check_qt_version, _validate_type
  from .docs import fill_doc
  from .misc import _pl
label_desc: Use image node_id 7 for calling a global function with example usage: _get_extra_data_path(home_dir) and returns: op