code: def test_get_transfer_hook(self):
      operator = S3ToGCSOperator(
          task_id=TASK_ID,
          bucket=S3_BUCKET,
          prefix=S3_PREFIX,
          delimiter=S3_DELIMITER,
          gcp_conn_id=GCS_CONN_ID,
          dest_gcs=GCS_PATH_PREFIX,
          google_impersonation_chain=IMPERSONATION_CHAIN,
      )
      transfer_hook = operator.get_transfer_hook()
  
      assert isinstance(transfer_hook, CloudDataTransferServiceHook)
      assert transfer_hook.gcp_conn_id == GCS_CONN_ID
      assert transfer_hook.impersonation_chain == IMPERSONATION_CHAIN
  
imports: from __future__ import annotations
  from unittest import mock
  from unittest.mock import PropertyMock
  import pytest
  import time_machine
  from airflow.exceptions import AirflowException, TaskDeferred
  from airflow.providers.google.cloud.hooks.cloud_storage_transfer_service import CloudDataTransferServiceHook
  from airflow.providers.google.cloud.transfers.s3_to_gcs import S3ToGCSOperator
  from airflow.utils.timezone import utcnow
label_desc: Use image node_id 8 for calling the TestS3ToGoogleCloudStorageOperatorDeferrable obj's underlying member method code with example usage: obj.test_get_transfer_hook() without return types