docs: def enable_napp(cls, mgr):
          """Install one NApp using NAppManager object."""
          try:
              if not mgr.is_enabled():
                  LOG.info('    Enabling...')
                  mgr.enable()
              LOG.info('    Enabled.')
          except (FileNotFoundError, PermissionError) as exception:
              LOG.error('  %s', exception)