docs: def enable_cache(self):
          """ Enable client-side caching for the current request """
          self.set_header('Cache-Control', 'max-age=%d, public' % self.CACHE_TIME)
  
          now = datetime.datetime.now()
          expires = now + datetime.timedelta(seconds=self.CACHE_TIME)
          self.set_header('Expires', expires.strftime('%a, %d %b %Y %H:%M:%S'))
  
          self.set_header('access-control-max-age', self.CACHE_TIME)