anchor.diff:  %% % TODO this is a temporary solution, returns GR's NS addresses
   %% return_gr_nameservers(DomainNotNormalized, #dns_zone{ip_addresses = IPAddresses, ns_servers = NSServers, ttl_ns = TTLNS, ttl_a = TTLA}) ->
   %%     {ok,
  -%%             [dns_server:answer_record(DomainNotNormalized, TTLNS, ns, NSHostname) || NSHostname <- NSServers] ++
  +%%             [dns_server:answer_record(DomainNotNormalized, TTLNS, ?S_NS, NSHostname) || NSHostname <- NSServers] ++
   %%             lists:flatten([begin
   %%                                IPAddrList = proplists:get_value(NSHostname, IPAddresses, []),
  -%%                                [dns_server:additional_record(NSHostname, TTLA, a, IPAddress) || IPAddress <- IPAddrList]
  +%%                                [dns_server:additional_record(NSHostname, TTLA, ?S_A, IPAddress) || IPAddress <- IPAddrList]
   %%                            end || NSHostname <- NSServers]) ++
   %%             [dns_server:authoritative_answer_flag(true)]
   %%     }.
positive.code:             case Domain of
                  CName ->
                      {ok,
                              [dns_server:answer_record(DomainNotNormalized, TTLNS, ns, NSHostname) || NSHostname <- NSServers] ++
                              lists:flatten([begin
                                                 IPAddrList = proplists:get_value(NSHostname, IPAddresses, []),
                                                 [dns_server:additional_record(NSHostname, TTLA, a, IPAddress) || IPAddress <- IPAddrList]
                                             end || NSHostname <- NSServers]) ++
                              [dns_server:authoritative_answer_flag(true)]
                      };
  
negative.code:                     handle_unknown_subdomain(DomainNotNormalized, Prefix, DNSZone);
                  IPAddrList ->
                      {ok,
                              [dns_server:answer_record(DomainNotNormalized, TTL, ?S_A, IPAddress) || IPAddress <- IPAddrList] ++
                              [dns_server:authoritative_answer_flag(true)]
                      }
              end
  