code: def get_schemaloc_string(self, ns_uris=None, sort=False, delim="\n"):
          if not ns_uris:
              ns_uris = six.iterkeys(self.__ns_uri_map)
          if sort:
              ns_uris = sorted(ns_uris)
          schemalocs = []
          for ns_uri in ns_uris:
              ni = self.__lookup_uri(ns_uri)
              if ni.schema_location:
                  schemalocs.append("{0.uri} {0.schema_location}".format(ni))
          if not schemalocs:
              return ""
          return 'xsi:schemaLocation="{0}"'.format(delim.join(schemalocs))