A Police officer checks a man wearing a carnival costume in Venice, Italy, Sunday, January 31, 2016. Carnival-goers in Venice are being asked by police to momentarily lift their masks as part of new anti-terrorism measures for the annual festivities. Police are also examining backpacks and bags and using metal-detecting wands before revelers are allowed into St. Mark's Square, the heart of the Venetian carnival. (Photo by Luigi Costantini/AP Photo)

People look at a man, who residents said was killed by al Qaeda militants, hanging on a bridge in Yemen's southeastern city of Mukalla June 17, 2015. Al Qaeda militants in Yemen killed two alleged Saudi spies, residents said, accusing them of planting tracking devices which enabled the assassination of the group's leader in a suspected U.S. drone strike. (Photo by Reuters/Stringer)

A woman directs traffic in the pouring rain in Pyongyang, North Korea on May 3, 2016. The city is preparing for the Workers' Party Congress starting on May 6th. It will be the first time since 1980 that the ruling party has convened. (Photo by Linda Davidson/The Washington Post)

A coach wipes away tears and comforts a girl who was feeling tired during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, May 4, 2016. (Photo by Aly Song/Reuters)

Filipinos riding on makeshift carts cross over an overflowing dam during a downpour in Las Pinas city, south of Manila, Philippines, 05 September 2017. According to the latest forecast from the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) state weather bureau, typhoon signals were raised over Northern Luzon brought by a tropical storm (local name: Tropical Storm Kiko) and warned fisherfolks and small seacrafts not to venture onto the sea due to big waves. (Photo by Francis R. Malasig/EPA/EFE)

Haitians pull a car atop a pushcart in Port-au-Prince, October 11, 1994. The price of gasoline has fallen to about $6 US per gallon since U.S. forces occupied Haiti. Before, gasoline had cost as much as $10 U.S. per gallon. (Photo by Eric Draper/AP Photo)

Students from St Andrews University are covered in foam as they take part in the traditional Raisin Weekend in the Lower College Lawn, at St Andrews in Scotland on October 22, 2018. The “raisin weekend” stems from a gift of raisins (now flour and foam) traditionally given by a first year student to their academic “parents” in gratitude for their guidance. (Photo by Russell Cheyne/Reuters)

A man passes at the displayed art installation “Middle way” by Romanian artist Bogdan Rata in Kiev, Ukraine, Tuesday, November 20, 2018. The monument set on the central Kiev street of Khreshchatyk, at the place of Vladimir Lenin monument which was destroyed in 2013 during the Maidan events. (Photo by Efrem Lukatsky/AP Photo)