code: def email_exists(self, email: str) -> bool:
      res = self.get_by_email(
          credentials=self.admin_verify_key().ok(), email=email
      )
      if res.ok() is None:
          return False
      else:
          return True
  
imports: from typing import List
  from typing import Optional
  from result import Ok
  from result import Result
  from ...node.credentials import SyftSigningKey
  from ...node.credentials import SyftVerifyKey
  from ...serde.serializable import serializable
  from ...store.document_store import BaseStash
  from ...store.document_store import DocumentStore
  from ...store.document_store import PartitionKey
  from ...store.document_store import PartitionSettings
  from ...store.document_store import QueryKeys
  from ...store.document_store import UIDPartitionKey
  from ...types.uid import UID
  from ...util.telemetry import instrument
  from ..action.action_permissions import ActionObjectPermission
  from ..response import SyftSuccess
  from .user import User
  from .user_roles import ServiceRole
label_desc: Use image node_id 7 for calling the UserStash obj's underlying member method code with example usage: obj.email_exists(email) and returns: False, True