def generate_arn(partition='', service='', region='', account_id='',
    resource=''):
    """Generate an ARN value.

    Args:
        partition (str): The partition that the resource is in. For standard
            AWS regions, the partition is aws. If you have resources in other
            partitions, the partition is aws-partitionname. For example, the
            partition for resources in the China (Beijing) region is aws-cn

        service (str): The service namespace that identifies the AWS product
            (for example, Amazon S3, IAM, or Amazon RDS)

        region (str): The region the resource resides in. Note that the ARNs
            for some resources do not require a region, so this component might
            be omitted

        account_id (str): The ID of the AWS account that owns the resource,
            without the hyphens. For example, 123456789012

        resource (str): The content of this part of the ARN varies by service.
            It often includes an indicator of the type of resource for example,
            an IAM user or Amazon RDS database followed by a slash (/) or a
            colon (:), followed by the resource name itself.

    Returns:
        str: The generated ARN

    """
    return 'arn:{}:{}:{}:{}:{}'.format(partition, service, region,
        account_id, resource)
