People with a South Korean flag waves as fireworks get off outside the stadium during the opening ceremony of the Pyeongchang 2018 Winter Olympic Games at the Pyeongchang Stadium on February 9, 2018. (Photo by Martin Bernetti/AFP Photo)

A person poses on the track during a fashion competition at the Durban July horse racing event in Durban, South Africa, July 2, 2016. (Photo by Rogan Ward/Reuters)

Men pull with a rope the body of an Islamic State fighter before burying him near Karamah, south of Mosul, Iraq November 11, 2016. (Photo by Goran Tomasevic/Reuters)

Crew members work to secure a hot-air balloon after landing at the city of Luxor, south of Cairo, Egypt December 13, 2016. (Photo by Amr Abdallah Dalsh/Reuters)

Saudi children of al-Fefi family walk up the stairs as they make their way to their schools through Fifa Mountain, in Jazan, south of Saudi Arabia, December 15, 2016. (Photo by Mohamed Al Hwaity/Reuters)

A participant in costume poses to a camera after a Halloween parade in Kawasaki, south of Tokyo, Japan October 30, 2016. More than 130,000 spectators turned up to watch the parade, where about 2,600 participants dressed up in costumes, according to the organiser. ((Photo by Kim Kyung-Hoon/Reuters)

A swimmer competes during the UK Cold Water Swimming Championships at Tooting Bec Lido in south London January 24, 2015. (Photo by Luke MacGregor/Reuters)

Planes land in fog at Heathrow Airport, west London, as heavy fog covers a many parts of the south east, on April 1, 2014. (Photo by Steve Parsons/PA Wire)