code: func dnsimpleSuitableZone(hostname string, zones map[string]dnsimple.Zone) *dnsimple.Zone {
  	var zone *dnsimple.Zone
  	for _, z := range zones {
  		if strings.HasSuffix(hostname, z.Name) {
  			if zone == nil || len(z.Name) > len(zone.Name) {
  				newZ := z
  				zone = &newZ
  			}
  		}
  	}
  	return zone
  }
docs: // dnsimpleSuitableZone returns the most suitable zone for a given hostname and a set of zones.