code: def test_get_conn_returns_a_boto3_connection(self):
      hook = StsHook(aws_conn_id="aws_default", region_name="us-east-1")
      assert hook.conn is not None
  
imports: from __future__ import annotations
  from airflow.providers.amazon.aws.hooks.sts import StsHook
label_desc: Use image node_id 1 for calling the TestSTS obj's underlying member method code with example usage: obj.test_get_conn_returns_a_boto3_connection() without return types