Visitors walk past the fully equipped dining table inside the “Crazy House”, which is completely built upside-down, in the village of Affoldern near the Edersee lake, May 7, 2014. Three friends came up with the idea to build the tourist attraction, which cost about 200,000 euros and took some six weeks to complete. (Photo by Kai Pfaffenbach/Reuters)

Revellers continue to party and dance through the night and day during the second day of the San Fermin Running Of The Bulls festival, on July 7, 2014 in Pamplona, Spain. The annual Fiesta de San Fermin, made famous by the 1926 novel of US writer Ernest Hemmingway “The Sun Also Rises”, involves the running of the bulls through the historic heart of Pamplona. (Photo by Christopher Furlong/Getty Images)

A military police officer aims his gun to a demonstrator during a protest in Brasilia, Brazil, Tuesday, April 7, 2015. The officer had picked up a bottle that was thrown towards them but did not fire his gun and backed away. Thousands of workers have staged rallies in 12 cities across Brazil to protest against a proposed law that would allow companies to outsource their labor force. (Photo by Eraldo Peres/AP Photo)

A freighter trapped in ice is shown in this aerial photo near Whitefish Bay on Lake Superior northwest of Sault Ste. Marie, Ontario April 7, 2015. The biggest ice cover on the Great Lakes in decades is backing up shipments of everything from Canadian grain to U.S. iron and steel in one of North America's most important economic regions. (Photo by Kenneth Armstrong/Reuters)

In this photo released by Xhinhua News Agency, a rescuer evacuates residents near the site of a chemical plant blast in Zhangzhou, southeast China's Fujian Province Tuesday, April 7, 2015. Six people have been hospitalized and hundreds of firefighters deployed to battle a blaze sparked by an explosion at Goure PX Plant that produces the toxic chemical paraxylene, officials said Tuesday. (Photo by Wei Peiquan/AP Photo/Xinhua)

A picture of Moon Ji-sung, a high school student who died in the Sewol ferry disaster, hangs in her room in Ansan April 7, 2015. Her dream was to be a flight attendant. Nearly a year after the Sewol ferry sank on April 16, 2014, with the death of 250 students, some families keep their children’s bedrooms intact to remember and honour their loved ones. More than 300 people, most of them students and teachers from Danwon High School, are dead, or missing and presumed dead, after the Sewol ferry sank on a routine trip from the port of Incheon, near Seoul, to the holiday island of Jeju. (Photo by Kim Hong-Ji/Reuters)

North Korean cheerleaders arrive at a rest stop, or service station, as their bus convoy carrying a 280- member delegation on its way to the 2018 Pyeongchang winter Olympic games, makes its way past Gapyeong on February 7, 2018 More than 200 young North Korean women arrived in South Korea to root for athletes from both sides of the peninsula at the Winter Olympics. (Photo by Ed Jones/AFP Photo)

This February 7, 2018, photo shows João Lousada, a flight controller for the International Space Station, wearing an experimental space suit during a simulation of a future Mars mission in the Dhofar desert of southern Oman. The desolate desert in southern Oman resembles Mars so much that more than 200 scientists from 25 nations organized by the Austrian Space Forum are using it for the next four weeks to field-test technology for a manned mission to Mars. (Photo by Sam McNeil/AP Photo)