Add methods to obtain median/last observed bw

                        for rt in _ResultType])

        return rt_dict

    @staticmethod

    def desc_obs_bw_bs_mean_from_results(results):

        desc_obs_bws = []

        for r in results:

            if r.relay_observed_bandwidth is not None:

                desc_obs_bws.append(r.relay_observed_bandwidth)

        if desc_obs_bws:

            return max(round(mean(desc_obs_bws)), 1)

        return None

    @staticmethod

    def desc_obs_bw_bs_last_from_results(results):

        # the last is at the end of the list

        for r in reversed(results):

            if r.relay_observed_bandwidth is not None:

                return r.relay_observed_bandwidth

        return None

    @property

    def bw_keyvalue_tuple_ls(self):

        """Return list of KeyValue Bandwidth Line tuples."""