code: def append(self, acces, **kwargs):
          
          if acces.Id in set(ac.Id for ac in self):
              raise ValueError("Acces id already in list !")
          list.append(self, acces)
          if kwargs:
              self.infos[acces.Id] = kwargs
docs: Append acces to list. Quite slow since it checks uniqueness.
          kwargs may set `info` for this acces.