def METHOD_NAME(aggregator, pricing_client_stubber):
    # Mock client responses
    code = 'TEST_DESCRIBE_SERVICES_ERROR_CODE'
    message = 'TEST_DESCRIBE_SERVICES_ERROR_MESSAGE'
    pricing_client_stubber.stub_describe_services_error(code, message)
    # Mock instance configuration
    instance = {'region_name': 'us-east-1', 'AmazonEC2': ['YQHNG5NBWUE3D67S.4NA7Y494T4.6YS6EN2CT7']}
    # Run check
    with pricing_client_stubber, patch('boto3.client', Mock(return_value=pricing_client_stubber.get_client())):
        with pytest.raises(CheckException):
            check = AwsPricingCheck('aws_pricing', {})
            check.check(instance)
    # Validate results
    message = 'An error occurred ({}) when calling the DescribeServices operation: {}'.format(code, message)
    aggregator.assert_service_check('aws_pricing.status', AwsPricingCheck.CRITICAL, message=message)
    assert len(aggregator.service_checks('aws_pricing.status')) == 1, 'Too many service checks were emitted'