- ' slashes: -f 22/17/18 . -f mp4 , -f m4a and -f flv are also'
- ' supported. You can also use the special names "best",'
- ' "bestvideo", "bestaudio", "worst", "worstvideo" and'
- ' "worstaudio". By default, youtube-dl will pick the best quality.'
+ ' slashes, as in -f 22/17/18 . '
+ ' Instead of format codes, you can select by extension for the '
+ 'extensions aac, m4a, mp3, mp4, ogg, wav, webm. '
+ 'You can also use the special names "best",'
+ ' "bestvideo", "bestaudio", "worst". '
+ ' By default, youtube-dl will pick the best quality.'