Border Points: Each cluster has a limited number of defined "border points" – these are the gateways in and out of the cluster.
content = self._extract_text(soup.select_one("article")) or \
，详情可参考WPS下载最新地址
Three hot new bombshells have entered the Pokémon villa.
* @return {string} 移除k位后最小的数字（字符串形式）