class_docstr: Asynchronous hook for Google Storage Transfer Service.
docstr: Returns async connection to the Storage Transfer Service.
  
  :return: Google Storage Transfer asynchronous client.
code: def get_conn(self) -> StorageTransferServiceAsyncClient:
      """
      Returns async connection to the Storage Transfer Service.
  
      :return: Google Storage Transfer asynchronous client.
      """
      if not self._client:
          self._client = StorageTransferServiceAsyncClient()
      return self._client
  
imports: from __future__ import annotations
  import json
  import logging
  import time
  import warnings
  from copy import deepcopy
  from datetime import timedelta
  from typing import TYPE_CHECKING, Any, Sequence
  from google.cloud.storage_transfer_v1 import ListTransferJobsRequest, StorageTransferServiceAsyncClient, TransferJob, TransferOperation
  from googleapiclient.discovery import Resource, build
  from googleapiclient.errors import HttpError
  from airflow.exceptions import AirflowException, AirflowProviderDeprecationWarning
  from airflow.providers.google.common.hooks.base_google import GoogleBaseAsyncHook, GoogleBaseHook
label_desc: Use image node_id 2 for calling the CloudDataTransferServiceAsyncHook obj's underlying member method code with example usage: obj.get_conn() and returns: self