code: def get_file_timestamp(self, key):
      response, _ = self._get_file_meta(key)
      if response is not None and "updated" in response.keys():
          timestamp = calendar.timegm(
              time.strptime(
                  response["updated"], "%Y-%m-%dT%H:%M:%S.%fZ"
              )
          )
          return timestamp
      else:
          return None
  
imports: import time
  import calendar
  import certifi
  import json
  from studio import pyrebase
  from studio.util import logs
  from studio.auth import get_auth
  from studio.storage.storage_setup import get_storage_verbose_level
  from studio.storage.storage_type import StorageType
  from studio.storage.storage_handler import StorageHandler
label_desc: Use image node_id 6 for calling the FirebaseStorageHandler obj's underlying member method code with example usage: obj.get_file_timestamp(key) and returns: timestamp, None