func (NATGateway) MarkAndSweep(sess *session.Session, acct string, region string, set *Set) error {
	svc := ec2.New(sess, &aws.Config{Region: aws.String(region)})

	inp := &ec2.DescribeNatGatewaysInput{}
	if err := svc.DescribeNatGatewaysPages(inp, func(page *ec2.DescribeNatGatewaysOutput, _ bool) bool {
		for _, gw := range page.NatGateways {
			g := &natGateway{
				Account: acct,
				Region:  region,
				ID:      *gw.NatGatewayId,
			}

			if set.Mark(g) {
				inp := &ec2.DeleteNatGatewayInput{NatGatewayId: gw.NatGatewayId}
				if _, err := svc.DeleteNatGateway(inp); err != nil {
					klog.Warningf("%v: delete failed: %v", g.ARN(), err)
				}
			}
		}
		return true
	}); err != nil {
		return err
	}

	return nil
}
func (NATGateway) MarkAndSweep(sess *session.Session, acct string, region string, set *Set) error {
	svc := ec2.New(sess, &aws.Config{Region: aws.String(region)})

	inp := &ec2.DescribeNatGatewaysInput{}
	if err := svc.DescribeNatGatewaysPages(inp, func(page *ec2.DescribeNatGatewaysOutput, _ bool) bool {
		for _, gw := range page.NatGateways {
			g := &natGateway{
				Account: acct,
				Region:  region,
				ID:      *gw.NatGatewayId,
			}

			if set.Mark(g) {
				inp := &ec2.DeleteNatGatewayInput{NatGatewayId: gw.NatGatewayId}
				if _, err := svc.DeleteNatGateway(inp); err != nil {
					klog.Warningf("%v: delete failed: %v", g.ARN(), err)
				}
			}
		}
		return true
	}); err != nil {
		return err
	}

	return nil
}
// MarkAndSweep looks at the provided set, and removes resources older than its TTL that have been previously tagged.