WARNING: [youtube] Falling back to generic n function search
         player = https://www.youtube.com/s/player/f3d47b5a/player_ias.vflset/en_US/base.js
WARNING: [youtube] 3mEuKdKJ5fA: nsig extraction failed: Some formats may be missing
         n = KTGQJGE2r3kmMiXBN ; player = https://www.youtube.com/s/player/f3d47b5a/player_ias.vflset/en_US/base.js
WARNING: [youtube] Falling back to generic n function search
         player = https://www.youtube.com/s/player/f3d47b5a/player_ias.vflset/en_US/base.js
WARNING: [youtube] 3mEuKdKJ5fA: nsig extraction failed: Some formats may be missing
         n = 7wHH_DrDJL8xVxHir ; player = https://www.youtube.com/s/player/f3d47b5a/player_ias.vflset/en_US/base.js