2020-02-10 OSI https://qiita.com/manamin0521/items/1df1ec65637ad1620329#osi%E5%8F%82%E7%85%A7%E3%83%A2%E3%83%87%E3%83%AB%E3%81%AE%E3%83%87%E3%83%BC%E3%82%BF%E3%81%AE%E6%B5%81%E3%82%8C