code: def _handle_exists_request(
      work: "LightningWork", request: _ExistsRequest
  ) -> _ExistsResponse:
      return _ExistsResponse(
          source=request.source,
          path=request.path,
          name=request.name,
          destination=request.destination,
          hash=request.hash,
          exists=getattr(work, request.name, None) is not None,
      )
  
imports: import hashlib
  import pathlib
  import pickle
  from abc import ABC, abstractmethod
  from time import sleep
  from typing import TYPE_CHECKING, Any, Optional, Union
  from lightning.app.core.constants import REMOTE_STORAGE_WAIT
  from lightning.app.core.queues import BaseQueue
  from lightning.app.storage.path import Path, _filesystem, _shared_storage_path
  from lightning.app.storage.requests import _ExistsRequest, _ExistsResponse, _GetRequest, _GetResponse
  from lightning.app.utilities.app_helpers import Logger
  from lightning.app.utilities.component import _is_flow_context
label_desc: Use image node_id 18 for calling the _BasePayload obj's underlying member method code with example usage: obj._handle_exists_request(work, request) and returns: _ExistsResponse