code: def get_token_owner(labml_token: str) -> Optional[str]:
      user_key = TokenOwnerIndex.get(labml_token)
  
      if user_key:
          user = user_key.load()
          return user.email
  
      return ""
  
imports: import time
  from labml_db import Model, Key, Index
  from typing import List, Dict, Optional, Set, Any
  from .None import project
  from ..None import utils
  from ..utils import gen_token
label_desc: Use image node_id 1 for calling a global function with example usage: get_token_owner(labml_token) and returns: str, user