code: def get_rmq_cluster_running_nodes(self, sentry_unit):
          
          # NOTE(beisner): rabbitmqctl cluster_status output is not
          # json-parsable, do string chop foo, then json.loads that.
          str_stat = self.get_rmq_cluster_status(sentry_unit)
          if 'running_nodes' in str_stat:
              pos_start = str_stat.find("{running_nodes,") + 15
              pos_end = str_stat.find("]},", pos_start) + 1
              str_run_nodes = str_stat[pos_start:pos_end].replace("'", '"')
              run_nodes = json.loads(str_run_nodes)
              return run_nodes
          else:
              return []
docs: Parse rabbitmqctl cluster_status output string, return list of
          running rabbitmq cluster nodes.
  
          :param unit: sentry unit
          :returns: List containing node names of running nodes