code: def default_location(self) -> str:
      return self._default_zone
  
imports: import collections
  import logging
  import random
  from typing import Any, Dict, List, Set, Tuple
  from hailtop.aiocloud import aiogoogle
  from hailtop.utils import url_basename
  from ....driver.exceptions import RegionsNotSupportedError
  from ....driver.location import CloudLocationMonitor
  from ....utils import WindowFractionCounter
label_desc: Use image node_id 3 for calling the ZoneMonitor obj's underlying member method code with example usage: obj.default_location() and returns: self