"A Music Video" is a song sung by Gumball and Darwin while pretending that they were on TV in the episode, "The Prank." It is the second shortest of the show's songs, next to the "Please Do It Larry!" song.
Gumball: A music video, a music video!
Darwin: Yeah, we are in a music video!
Gumball: This is what you call a music video!
Darwin: Oh baby! We're singing! I'm in a music videooooo…
[Gumball and Darwin realize that Richard unplugged the TV]
Gumball: [Spoken] Run.