def METHOD_NAME(self, aggregator, instance):
    # type: (AggregatorStub, Instance) -> None
    check = VoltDBCheck('voltdb', {}, [instance])
    with mock.patch('requests.get', side_effect=requests.RequestException('Something failed')):
        error = check.run()
    assert 'Something failed' in error
    assertions.assert_service_checks(aggregator, instance, connect_status=VoltDBCheck.CRITICAL)
    aggregator.assert_all_metrics_covered()  # No metrics collected.