code: def teardown_class(cls) -> None:
      clear_db_connections(add_default_connections_back=True)
  
file_path: airflow/tests/providers/apache/spark/hooks/test_spark_sql.py
imports: from __future__ import annotations
  import itertools
  from io import StringIO
  from unittest.mock import call, patch
  import pytest
  from airflow.exceptions import AirflowException
  from airflow.models import Connection
  from airflow.providers.apache.spark.hooks.spark_sql import SparkSqlHook
  from airflow.utils import db
  from tests.test_utils.db import clear_db_connections
label_desc: Use image node_id 2 for calling the TestSparkSqlHook obj's underlying member method code with example usage: obj.teardown_class(cls) without return types