Sen. Bernie Sanders meets a little fan, dressed as Sanders, during a rally at Bonanza High School in Las Vegas. | (AP Photo/Evan Vucci)

Supporters of incumbent Nigerian President Mahamadou Issoufou attend a campaign rally in Niamey, Niger. | (REUTERS/Joe Penne)

French bulldog Watson is wheeled to a ring for judging at the 2016 Westminster Kennel Club Dog Show in New York City. | (REUTERS/Mike Segar)

Nuns participate in a Mass led by Pope Francis at Venustiano Carranza stadium in Morelia, Mexico. | (REUTERS/Max Rossi)

The seat of the late Supreme Court Justice Antonin Scalia is draped with black wool crepe in memoriam inside the Supreme Court. | (REUTERS/Carlos Barria)

A worker carries a fresh parmesan wheel at a dairy cooperative in Modena, Italy. | (REUTERS/Alessandro Bianchi)

Hindu priests hold traditional incense lamps as they perform a ritual known as "Aarti" on the banks of Sangam during the annual religious festival of Magh Mela in Allahabad, India. | (REUTERS/Jitendra Prakash)

A man catches crabs at an estuary on Zikim beach near Ashkelon, Israel. | (REUTERS/Amir Cohen)

An orangutan drinks milk in Kunming, China. | (REUTERS/Wong Campion)

Lady Gaga performs a medley of David Bowie songs as a tribute to the late singer during the Grammy Awards in Los Angeles. | (REUTERS/Mario Anzuoni)

A boy looks through a cloth backdrop to try to get a glimpse of Donald Trump as he arrives backstage for a rally with sportsmen in Walterboro, South Carolina. | (REUTERS/Jonathan Ernst)

Australian dog trainer and former surfing champion Chris de Aboitiz rides a wave with his dogs off of Palm Beach in Sydney, Australia. | (REUTERS/Jason Reed)

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