code: def send_static_file(self, filename):
          
          if self.config['MODE'] == 'api-only':
              # if 'api-only' mode is set, we should not send static files
              abort(404)
  
          theme_static_folder = getattr(self, 'theme_static_folder', None)
          if theme_static_folder:
              try:
                  return send_from_directory(theme_static_folder, filename)
              except NotFound:
                  pass
          return super(CustomFlask, self).send_static_file(filename)
docs: Send static files from the static folder
          in the current selected theme prior to the global static folder.
  
          :param filename: static filename
          :return: response object