Pope Francis passes past a portrait of himself as he arrives to meet youths in Santo Tomas University in Manila, Philippines, Sunday, January 18, 2015. Francis is in the Philippines on Sunday, the final full day of a weeklong trip that also took him to Sri Lanka. (Photo by Alessandra Tarantino/AP Photo)

Members of the Jordanian police women's team attend the 7th Annual Warrior Competition at the King Abdullah Special Operations Training Center in Amman April 22, 2015. Thirty-eight teams from 18 countries are participating in the competition to test their military skills. (Photo by Muhammad Hamed/Reuters)

Pupils of the Dao ethnic tribe return home from school along a hillside path at Suoi Thau village in Hoang Su Phi district of Vietnam's northern province of Ha Giang, located at the border with China, September 18, 2015. (Photo by Reuters/Kham)

Ricky Martin perfoms "La Mordidita" during the Latin Recording Academy Person of the Year gala honoring Brazilian singer Roberto Carlos in Las Vegas, Nevada November 18, 2015. (Photo by Mario Anzuoni/Reuters)

Marshalls try to get their hands on a streaker as golfers Michael Campbell of New Zealand and Paul McGinley of Ireland play the World Match Play final at Wentworth golf club some 20 miles west of London, 18 September 2005. Campbell won the title at the 17th hole. (Photo by Odd Andersen/AFP Photo)

Women pose for a picture at Havana city, Cuba, March 17, 2016. Obama arrives in Havana on Sunday for a historic visit that seals a rapprochement he and Cuban President Raul Castro agreed in December 2014 after 18 months of secret negotiations. (Photo by Ivan Alvarado/Reuters)

In this photograph taken on February 18, 2016, Pakistani children ride on swings in the predominantly Pashtun Korangi District of Karachi. In a rundown district of Karachi, Rabia balks at a neighbour's proposal to vaccinate her children, demonstrating one of the biggest hurdles to eradicating polio in Pakistan by the end of the year: confused and frightened parents. (Photo by Asif Hassan/AFP Photo)

Serena Williams of the U.S. serves during her first round match against Italy's Camila Giorgi at the Australian Open tennis tournament at Melbourne Park, Australia, January 18, 2016. (Photo by Jason O'Brien/Reuters)