Williams' "Despicable Me 2" track is nominated for best original song against U2's "Ordinary Love" from Mandela: Long Walk to Freedom, Karen O's "The Moon Song" from Her and written with Spike Jonze, and "Let It Go" by Robert Lopez and Kristen Anderson-Lopez from Frozen.
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Besides being a song "'about Gru and being happy and this relentless mood that can’t be changed,'" Williams told Billboard of the track, "Happy" is also featured on Williams' latest album, "G I R L," which officially hits shelves March 3 -- though it has been available to stream via iTunes Radio for the past week. "G I R L" is Williams' first album release in eight years.
Williams also released the first-ever 24-hour music video for the song, which features guest spots from Odd Future's Tyler, the Creator and Earl Sweatshirt, Steve Martin, Steve Carell and more. The interface for the video, found on the website 24hoursofhappy.com, sets the clip at a time corresponding to the local time of the viewer, with the ability to fast-forward, rewind and skip around to different times of the day.