code: def _add_url_rule(self, app):
          
          app.url_map.converters['regex'] = RegexConverter
          app.add_url_rule(
              app.config['IMAGINE_URL'] + '/<regex("[^\/]+"):filter_name>/<path:path>',
              app.config['IMAGINE_NAME'],
              self.handle_request
          )
  
          return app
docs: Add url rule for get filtered images
          :param app: Flask application
          :return: Flask application