https://blog.faceutil.com/2017/03/28/mp3-%ed%8e%b8%ec%a7%91%ed%94%84%eb%a1%9c%ea%b7%b8%eb%9e%a8-mp3%ed%8c%8c%ec%9d%bc-%ec%9e%90%eb%a5%b4%ea%b8%b0-%ed%95%a9%ec%b9%98%ea%b8%b0-mp3-clipper-and-joiner-%e3%81%85/