code: def show_loading_page(self):
          
          loading_template = Template(LOADING)
          loading_img = get_image_path('loading_sprites.png')
          if os.name == 'nt':
              loading_img = loading_img.replace('\\', '/')
          message = _("Connecting to kernel...")
          page = loading_template.substitute(css_path=CSS_PATH,
                                             loading_img=loading_img,
                                             message=message)
          self.setHtml(page)
docs: Show a loading animation while the kernel is starting.