code: def test_get_conn_returns_a_boto3_connection(self):
      hook = EmrHook(
          aws_conn_id="aws_default", region_name="ap-southeast-2"
      )
      assert hook.get_conn().list_clusters() is not None
  
imports: from __future__ import annotations
  import re
  from unittest import mock
  import boto3
  import pytest
  from botocore.exceptions import WaiterError
  from moto import mock_emr
  from airflow.exceptions import AirflowException
  from airflow.providers.amazon.aws.hooks.emr import EmrHook
label_desc: Use image node_id 2 for calling the TestEmrHook obj's underlying member method code with example usage: obj.test_get_conn_returns_a_boto3_connection() without return types