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)

Newlyweds pose on a zebra crossing for wedding photographers during the 2018 soccer World Cup in Samara, Russia, Sunday, July 8, 2018. (Photo by Frank Augstein/AP Photo)

Guanacos sit during a signing ceremony in Patagonia Park, Chile, January 29, 2018. Chilean President Michelle Bachelet signed decrees Monday creating vast new national parks using lands donated by U.S. conservation organization Tompkins Conservation in what is believed to be the largest private donation of land ever from a private entity to a country. (Photo by Esteban Felix/AP Photo)

In this photo taken Wednesday, December 5, 2018, a woman who scavenges recyclable materials from garbage for a living is seen through a cloud of smoke from burning trash, surrounded by Marabou storks who feed on the garbage, at the dump in the Dandora slum of Nairobi, Kenya. As the world meets again to tackle the growing threat of climate change, how the continent tackles the growing solid waste produced by its more than 1.2 billion residents, many of them eager consumers in growing economies, is a major question in the fight against climate change. (Photo by Ben Curtis/AP Photo)

A young Thai man jumps in the air and cheers as his rocket takes off at the Bun Bang Fai Rocket Festival on May 10, 2015 in Yasothon, Thailand. (Photo by Taylor Weidman/Getty Images)

Participants take part in a New Year's Jump into the Sea in Portoroz , Slovenia, January 1, 2016. (Photo by Srdjan Zivulovic/Reuters)

Saintsetseg Jambaldorj, a member of the Tsaatan ethnic minority, one of the last remaining groups of nomadic reindeer herders in East Taiga, Mongolia, wearing a traditional deel, on July 5, 2016. (Photo by Madoka Ikegami/Barcroft Images)

This picture taken on October 20, 2016 shows students practising wushu at the Tagou martial arts school in Dengfeng. China is investing hugely in football training and has vowed to have 50 million school- age players by 2020, as the ruling Communist party eyes “football superpower” status by 2050. (Photo by Nicolas Asfouri/AFP Photo)