code: def _load_token(self):
      tokendir_contents = os.listdir(self.tokendir)
      tokens = [
          f
          for f in tokendir_contents
          if os.path.isfile(os.path.join(self.tokendir, f))
          and f.endswith(".githubtoken")
      ]
  
      # TODO selection out of multiple token files
      if not any(tokens):
          return None, None
  
      token_file = os.path.join(self.tokendir, tokens[0])
      with open(token_file) as f:
          token = f.read().strip()
  
      self.userid = self.verify_token(token)
      if self.userid != re.sub(r".githubtoken\Z", "", tokens[0]):
          self.logger.error(
              "Token filename does not match github login"
          )
          return None, None
  
      return token, token_file
  
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 7 for calling the GithubAuth obj's underlying member method code with example usage: obj._load_token() and returns: token,  token_file, None,  None, None,  None