code: def reply(
      self,
      context: AuthedServiceContext,
      reply: ReplyNotification,
  ) -> Union[ReplyNotification, SyftError]:
      msg = self.stash.get_by_uid(
          credentials=context.credentials, uid=reply.target_msg
      )
      if msg.is_ok():
          msg = msg.ok()
          reply.from_user_verify_key = context.credentials
          msg.replies.append(reply)
          result = self.stash.update(
              credentials=context.credentials, obj=msg
          )
          if result.is_ok():
              return result.ok()
          else:
              SyftError(
                  message="Couldn't add a new notification reply in the target notification."
              )
      else:
          SyftError(
              message="The target notification id {reply.target_msg} was not found!"
          )
  
imports: from typing import List
  from typing import Union
  from ...serde.serializable import serializable
  from ...store.document_store import DocumentStore
  from ...types.uid import UID
  from ...util.telemetry import instrument
  from ..action.action_permissions import ActionObjectREAD
  from ..context import AuthedServiceContext
  from ..response import SyftError
  from ..response import SyftSuccess
  from ..service import AbstractService
  from ..service import SERVICE_TO_TYPES
  from ..service import TYPE_TO_SERVICE
  from ..service import service_method
  from ..user.user_roles import DATA_SCIENTIST_ROLE_LEVEL
  from ..user.user_roles import GUEST_ROLE_LEVEL
  from .notification_stash import NotificationStash
  from .notifications import CreateNotification
  from .notifications import LinkedObject
  from .notifications import Notification
  from .notifications import NotificationStatus
  from .notifications import ReplyNotification
label_desc: Use image node_id 3 for calling the NotificationService obj's underlying member method code with example usage: obj.reply(context, reply) and returns: result