@Override
 public String getPlayerPrefix(String world, String player) {
   UUID uuid = API.getUUIDFromName(player);
   String prefix = API.getPlayerInfo(uuid, "prefix");
   if (prefix == null) {
     String prigroup = API.getPlayerGroup(uuid);
     prefix = API.getGroupInfo(prigroup, "prefix");
   }
   return prefix;
 }
 @Override
 public String getGroupPrefix(String world, String group) {
   return API.getGroupInfo(group, "prefix");
 }
 @Override
 public String getGroupInfoString(String world, String group, String node, String defaultValue) {
   String val = API.getGroupInfo(group, node);
   return val != null ? val : defaultValue;
 }