An armed man herds his cattle close to the village of Nimini in northern South Sudan, February 8, 2017. In the chaos of South Sudan's civil war, it took three years for Nyagonga Machul to find her lost children. Machul had traveled from her village to the capital when President Salva Kiir, an ethnic Dinka, fired his deputy Riek Machar, a Nuer, in 2013. (Photo by Siegfried Modola/Reuters)

Dancers perform at a Carnival parade in Les Cayes, Haiti, Tuesday, February 28, 2017. Haiti's three-day Carnival festivities have brought rum-fueled parties, imaginative costumes and high-energy dance music to a southern city that's still recovering from last year's punishing Hurricane Matthew. (Photo by Dieu Nalio Chery/AP Photo)

Wild weather drenches tourists, Sydney, Australia on March 7, 2017. A series of photographs as tourists take a soaking on Sydney's iconic Manly Ferry sailing big swells near Sydney's North Head. The Weather Bureau warns of large and powerful surf conditions expected to be hazardous for coastal activities such as rock fishing, swimming and surfing. (Photo by Hugh Peterswald/Pacific Press via ZUMA Wire/Rex Features/Shutterstock)

A protestor gestures toward the White House on the Ellipse near the South Lawn of the White House during the Women's March on Washington January 21, 2017 in Washington, DC. Large crowds are attending the anti-Trump rally a day after U.S. President Donald Trump was sworn in as the 45th U.S. president. (Photo by Drew Angerer/Getty Images)

The Japanese punk rock garage quartet Otoboke Beaver perform at Maggie Mae's at the South by Southwest (SXSW) Music Film Interactive Festival 2017 in Austin, Texas, U.S., March 17, 2017. (Photo by Brian Snyder/Reuters)

Sarah Bui poses for photographer, Brian Le around blossoming cherry trees, near the Tidal Basin on Thursday March 23, 2017 in Washington, DC. (Photo by Matt McClain/The Washington Post)

A man carries schoolchildren on his bicycle on a road in Srinagar, March 28, 2017. (Photo by Danish Ismail/Reuters)

Iraqi paramilitary troops fire towards Islamic State militants during a battle with Islamic State militants on the outskirts of the ancient city of Hatra near Mosul,Iraq April 26, 2017. (Photo by Reuters/Stringer)