code: def serve(self, app, conf):
          
  
          if self.args.reload:
              try:
                  self.watch_and_spawn(conf)
              except ImportError:
                  print('The `--reload` option requires `watchdog` to be '
                        'installed.')
                  print('   $ pip install watchdog')
          else:
              self._serve(app, conf)
docs: A very simple approach for a WSGI server.