docs: def list_containers(active=True, defined=True,
                      as_object=False, config_path=None):
      """
          List the containers on the system.
      """
  
      if config_path:
          if not os.path.exists(config_path):
              return tuple()
          try:
              entries = _lxc.list_containers(active=active, defined=defined,
                                             config_path=config_path)
          except ValueError:
              return tuple()
      else:
          try:
              entries = _lxc.list_containers(active=active, defined=defined)
          except ValueError:
              return tuple()
  
      if as_object:
          return tuple([Container(name, config_path) for name in entries])
      else:
          return entries