2000 attended a welcome party at TigerTiger Manchester which was the first event in set of big club night for new students to Manchester and Salford universities in Manchester, UK on September 19, 2016. This year, university bosses have stepped up security in Manchester. (Photo by Jordan Sinclair/UK News Pictures)

Men are held by Iraqi national security agents, to be interrogated at a checkpoint, as oil fields burn in Qayara, south of Mosul, Iraq, Saturday, November 5, 2016. Islamic State fighters launch counterattacks in the thin strip of territory Iraqi special forces have recaptured in eastern Mosul, highlighting the challenges ahead as the battle moves into more densely populated neighborhoods where coalition air power must be used more selectively. (Photo by Felipe Dana/AP Photo)

Attnedees dressed in Zombie outfits walk down the Gaslamp Quarter outside of the 2015 Comic-Con International in San Diego, California July 8, 2015. (Photo by Sandy Huffaker/Reuters)

Singer Kevin Lyttle (C) performs during the Premier Beverage: Jocktails 2012 Orlando at the Orlando Magic Experience Center on February 24, 2012 in Orlando, United States. (Photo by Gerardo Mora/Getty Images for Premier Beverage Company)

Singer Jason Derulo performs during his Flash Mob with Knicks City Dancers outside of Madison Square Garden on September 28, 2011 in New York City. (Photo by Mike Coppola/Getty Images)

A detail of "Supersilvio" by Francesco De Molfetta representing the Italian Prime Minister Silvio Berlusconi is displayed during the MiArt 2011 Contemporary and Modern Art International Fair press preview on April 7, 2011 in Milan, Italy.