code: func isAWSAlias(ep *endpoint.Endpoint, addrs []*endpoint.Endpoint) string {
  	if prop, exists := ep.GetProviderSpecificProperty("alias"); ep.RecordType == endpoint.RecordTypeCNAME && exists && prop.Value == "true" {
  		for _, addr := range addrs {
  			if addr.DNSName == ep.Targets[0] {
  				if hostedZone := canonicalHostedZone(addr.Targets[0]); hostedZone != "" {
  					return hostedZone
  				}
  
  			}
  		}
  	}
  	return ""
  }
docs: // isAWSAlias determines if a given hostname belongs to an AWS Alias record by doing an reverse lookup.