code: def _save_token(self):
      if self.token is None:
          return
  
      token_file = os.path.join(
          self.tokendir, self.userid + ".githubtoken"
      )
      with open(token_file, "w") as f:
          f.write(self.token)
  
imports: import os
  import getpass
  import time
  import json
  import shutil
  import atexit
  import tempfile
  import requests
  import re
  import uuid
  from builtins import input
  import google.auth.transport.requests
  import google.oauth2.id_token
  from studio.util.util import rand_string, check_for_kb_interrupt
  from studio import pyrebase
  from studio.util import logs
label_desc: Use image node_id 9 for calling the GithubAuth obj's underlying member method code with example usage: obj._save_token() without return types