"La La Land" producer Jordan Horowitz (L) shows the card reading Best Film 'Moonlight" next to US actor Warren Beatty after the latter mistakingly read "La La Land" initially at the 89th Oscars on February 26, 2017 in Hollywood, California. Pic/AFP 

What does it feel like to give away an Oscar? Ask La La Land producer Jordan Horowitz, who first announced that there was a mistake. "This is not a joke," he said.