A man smashes an apple with a sword placed on the head of a man wearing a knave costume during the Easter knight event on April 21, 2014 in Berlin. The easter knight event delivers an insight into medieval lifestyle. (Photo by Rainer Jensen/AFP Photo/DPA)

British singer and songwriter Charlotte Emma Aitchison aka Charli XCX poses in the green room for a portrait before the Sonos And Pandora Present “An Evening With Charli XCX” event at Sonos Studio on June 10, 2014 in Los Angeles, California. (Photo by Joe Scarnici/Getty Images for Sonos)

Beryl Lipton, left, douses Matt Lee during the ice bucket challenge at Boston's Copley Square, Thursday, August 7, 2014 to raise funds and awareness for ALS. The idea is: pay up for charity or get doused. The fund-raising phenomenon is catching on fast, propelled by popular videos of the dunkers and the dunked – including famous athletes and entertainers – posted on social media sites. And the challenges are raising tens of thousands of dollars and immeasurable awareness for causes from ALS to breast cancer to a camp for kids who've lost a father to war. (Photo by Elise Amendola/AP Photo)

Friends of Li Guojun drive a homemade tank-shaped vehicle in Kangping county, China. Li, a farmer who is a fan of tanks, spent six months with help from his friends to construct the almost 20-foot vehicle which weighs 2.5 tons. (Photo by Sheng Li/Reuters)

World's Greatest Swimming Pools: Four Seasons, Serengeti Pool, Tanzania. A show of elephants, buffalo and baboons awaits thanks to an active watering hole below the free-form infinity pool at this plush hideaway inside Serengeti National Park. Bonus: Because of infrared technology at the hole, guests can be notified on their bedroom TV when animals are approaching. When you've got word of wildlife on the horizon, catch them from your private terrace – or head back to the pool. (From $1,650). (Photo by Four Seasons)

In this July 11, 2018 photo, members of a private photo studio take pictures of a woman in Havana, Cuba. New rules for private business indicate that the government has ruled out going further to open private business, such as allowing small and medium enterprises and authorizing business to operate as societies. Currently, private business licenses are granted only to individuals, and only one license per person. (Photo by Desmond Boylan/AP Photo)

A Somali Armed Forces member carries her ammunition during fighting between the military and police backed by intelligence forces in the Dayniile district of Mogadishu, Somalia September 16, 2017. (Photo by Feisal Omar/Reuters)

A Palestinian man rides his horse on a beach in Gaza City February 17, 2017. (Photo by Mohammed Salem/Reuters)