code: def _handle_tb_index(req, tb_servers, data, key):
      try:
          return _handle_tb(req, tb_servers, key)
      except NotFound:
          if key != "0":
              key = _try_run_id(key, data)
          with tb_servers:
              return tb_servers.start_server(key)
  
imports: import json
  import logging
  import math
  import os
  import socket
  import subprocess
  import sys
  import threading
  import time
  from werkzeug.exceptions import NotFound
  from werkzeug.utils import redirect
  from guild import serving_util
  from guild import util
  from guild import var
label_desc: Use image node_id 14 for calling a global function with example usage: _handle_tb_index(req, tb_servers, data, key) and returns: _handle_tb, tb_servers