docs: def register(action):
          """Action registration is used to support generating lists of
          permitted actions from a permission set and an object pattern.
          Only registered actions will be returned by such queries.
  
          """
          if isinstance(action, str):
              Action.register(Action(action))
          elif isinstance(action, Action):
              Action.registered.add(action)
          else:
              for a in action:
                  Action.register(a)