code: def auth_access_token() -> Optional[str]:
      """Attempts to fetch the local Oauth2 access token from the user's environment.
      Returns the token if it exists, or None if not
  
      """
      try:
          ret = check_output(
              ["gcloud", "auth", "print-access-token"], encoding="utf8"
          ).rstrip()
          return ret if len(ret) > 0 else None
      except CalledProcessError:
          return None
  
imports: from subprocess import CalledProcessError, check_output
  from typing import Optional
  from google.oauth2 import service_account
  from google.oauth2.credentials import Credentials
label_desc: Use image node_id 1 for calling a global function with example usage: auth_access_token() and returns: unknown, None