func deleteFirewallRules(
	d *schema.ResourceData,
	meta interface{},
	rules *schema.Set,
	ors *schema.Set) error {
	var errs *multierror.Error

	var wg sync.WaitGroup
	wg.Add(ors.Len())

	sem := make(chan struct{}, d.Get("parallelism").(int))
	for _, rule := range ors.List() {
		// Put a sleep here to avoid DoS'ing the API
		time.Sleep(500 * time.Millisecond)

		go func(rule map[string]interface{}) {
			defer wg.Done()
			sem <- struct{}{}

			// Delete a single rule
			err := deleteFirewallRule(d, meta, rule)

			// If we have at least one UUID, we need to save the rule
			if len(rule["uuids"].(map[string]interface{})) > 0 {
				rules.Add(rule)
			}

			if err != nil {
				errs = multierror.Append(errs, err)
			}

			<-sem
		}(rule.(map[string]interface{}))
	}

	wg.Wait()

	return errs.ErrorOrNil()
}
func deletePortForwards(
	d *schema.ResourceData,
	meta interface{},
	forwards *schema.Set,
	ors *schema.Set) error {
	var errs *multierror.Error

	var wg sync.WaitGroup
	wg.Add(ors.Len())

	sem := make(chan struct{}, 10)
	for _, forward := range ors.List() {
		// Put a sleep here to avoid DoS'ing the API
		time.Sleep(500 * time.Millisecond)

		go func(forward map[string]interface{}) {
			defer wg.Done()
			sem <- struct{}{}

			// Delete a single forward
			err := deletePortForward(d, meta, forward)

			// If we have a UUID, we need to save the forward
			if forward["uuid"].(string) != "" {
				forwards.Add(forward)
			}

			if err != nil {
				errs = multierror.Append(errs, err)
			}

			<-sem
		}(forward.(map[string]interface{}))
	}

	wg.Wait()

	return errs.ErrorOrNil()
}