GET /topic/%23%E3%81%82%E3%81%AA%E3%81%9F%E3%81%8C%E7%84%A1%E6%84%8F%E8%AD%98%E3%81%AB%E5%85%83%E6%B0%97%E3%82%92%E8%B2%B0%E3%81%A3%E3%81%A6%E3%82%8B%E4%BA%BA