Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

A model walks the runway at the Agatha Ruiz de La Prada show during the Mercedes-Benz Madrid Fashion Week Autumn/Winter 2017 at Ifema on February 17, 2017 in Madrid, Spain. (Photo by Pablo Cuadra/Getty Images)

A truck remains mired in mud and debris on State Route 58 near Tehachapi, California, about 60 miles (97 km) outside of Los Angeles October 17, 2015. A mudslide on Thursday left nearly 200 vehicles, including 75 semi-trailer trucks, stuck in up to five feet of mud, local sheriff's spokesman Ray Pruitt said. (Photo by David McNew/Reuters)

A devotee offers prayers to the setting sun during the "Chhat" festival at Bagmati river in Kathmandu, Nepal November 17, 2015. Hindus in Nepal celebrate "Chhat", a four-day festival that honours the sun god, by praying at sunrise and sunset, and seek blessings for one's family by giving offerings. (Photo by Navesh Chitrakar/Reuters)

A replica of the Wall-E character is remotely controlled with a mobile phone by Bolivian student Esteban Quispe, 17, in Patacamaya, south of La Paz, December 10, 2015. Quispe built the Wall-E robot using materials he obtained from a rubbish dump in the town located in the Andean highland region. He hopes to mechanize agriculture in Patacamaya by making use of robots that operate on solar energy, Quispe told Reuters. (Photo by David Mercado/Reuters)

Venezuela: An anti-government protester wearing a Guy Fawkes mask throws a molotov cocktail at the Bolivarian National Police during clashes in Caracas, Venezuela, Thursday, April 17, 2014. Opposition protesters have been demonstrating against high crime, high inflation and shortages of basic goods since mid-February. (Photo by Ramon Espinosa/AP Photo)

A man wearing a native costume named “Woman Carrying Husband” poses ahead of the Carnival in Sostanj January 15, 2015. Slovenians and members of various ethnological groups celebrate the annual carnival, also known locally as Pust, by wearing traditional masks and costumes to symbolically “chase away” the winter. Prust runs from February 7 to 17 this year. (Photo by Srdjan Zivulovic/Reuters)

A man wears a sweater covered in Irish themed pins as he stands with thousands of spectators to watch the 254th New York City St. Patrick's Day parade up 5th Avenue in the Manhattan Borough of New York, March 17, 2015. (Photo by Mike Segar/Reuters)