code: def get_initial_status_brok(self, extra=None):
          
          # Here members is a list of identifiers and we need their names
          if extra and isinstance(extra, Items):
              members = []
              for member_id in self.members:
                  member = extra[member_id]
                  members.append((member.uuid, member.get_name()))
              extra = {'members': members}
  
          return super(Itemgroup, self).get_initial_status_brok(extra=extra)
docs: Get a brok with the group properties
  
          `members` contains a list of uuid which we must provide the names. Thus we will replace
          the default provided uuid with the members short name. The `extra` parameter, if present,
           is containing the Items to search for...
  
          :param extra: monitoring items, used to recover members
          :type extra: alignak.objects.item.Items
          :return:Brok object
          :rtype: object