public String find_family(String os) {
      Map<String,String>  pos = parse_os(os);
      for ( String family : osMap.keySet()) {
        JsonOsFamilyEntry fam = osMap.get(family);
        if (fam.getDistro().contains(pos.get(OS_DISTRO)) && fam.getVersions().contains(pos.get(OS_VERSION))){
          return family;
        }
      }
      return null;
    }
Finds the family for the specific OS
@param os the OS
@return the family, or <code>null</code> if not defined
ambari-server/src/main/java/org/apache/ambari/server/state/stack/OsFamily.java