WARNING: [youtube] Falling back to generic n function search
         player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js
WARNING: [youtube] 00j-q6pxVFc: nsig extraction failed: Some formats may be missing
         n = 4jo1gWkWRe-mvt9_S ; player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js
WARNING: [youtube] Falling back to generic n function search
         player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js
WARNING: [youtube] 00j-q6pxVFc: nsig extraction failed: Some formats may be missing
         n = 5CNmwh4VLA5RwOhgQ ; player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js