"Poopsie Cola" is an original song performed by The Chipmunks, as a short "Witch Doctor" parody/remix, in The Chipmunks episode Chipmunkmania and has yet to be released as part of an Alvin and the Chipmunks album.
Lyrics
The Chipmunks:
Ooo eee, ooo ah ah
Thirsty? Have a Poopsie Cola
Ooo eee, ooo ah ah
A taste that'll really refresh