docs: def enable(self):
          """Enable a NApp if not already enabled.
  
          Raises:
              FileNotFoundError: If NApp is not installed.
              PermissionError: No filesystem permission to enable NApp.
  
          """
          core_napps_manager = CoreNAppsManager(base_path=self._enabled)
          core_napps_manager.enable(self.user, self.napp)