Seiichiro Nishimoto, CEO of Shelter Co., poses wearing a gas mask at a model room for the company's nuclear shelters in the basement of his house in Osaka, Japan on April 26, 2017. With nearby North Korea increasing its show of power day by day with missile launches and nuclear tests, people in Japan are preparing for the worst by building private nuclear shelters, Reuters reports. (Photo by Kim Kyung-Hoon/Reuters)

A workman sweeping the highest sidewalk in the world, the 81st story of the Empire State Building, the world's tallest building, to the top of which the greatest dirigible “Los Angeles” will attempt to moor, New York, New York, early 1930s. This photo was made 1,248 feet above street level. (Photo by Adam Glickman/Underwood Archives/Getty Images)

Worker Shi Shenwei pulls a wheelbarrow at the construction site of a Buddhist temple in the village of Huangshan, near Quanzhou, Fujian Province, China, September 28, 2016. For most construction workers, lunch is a welcome break to rest and refuel. Not for Shi Shenwei. the 23-year-old spends his midday break jumping and swinging through a maze of scaffolding poles, performing a fitness routine that has made him China's latest social media sensation. (Photo by Thomas Peter/Reuters)

Jorge (2nd R), 31, who is among members of lesbian, gay, bisexual and transgender (LGBT) community and his brother Paulo, 28, (R) laugh at Arouche Square in downtown Sao Paulo, Brazil, November 20, 2016. (Photo by Nacho Doce/Reuters)

Labourers stack dried bricks inside a kiln, where they will be fired, at a brick factory on the outskirt of Sanaa, Yemen, June 1, 2016. Traditional mud brick tower houses have always been a source of pride to Yemenis, and over a year into a devastating civil war, they are also providing some much-needed jobs in the ancient capital Sanaa. (Photo by Mohamed al-Sayaghi/Reuters)

A woman poses for her husband alongside a giant camera Thursday, November 7, 2013 outside the Historic Green County Courthouse in Monroe, Wis. Chicago photographer Dennis Manarchy created what's being called the world's largest camera. It's 35-feet long and 12-feet tall it's a working replica of a vintage accordion-style camera that produces 16- by 24-foot prints, the equivalent of a two-story building. The giant camera is on display in Monroe through November 17 because a Monroe company manufactured the specially-built trailer. Manarchy plans to tow the camera around the country to shoot photos of indigenous cultures. (Photo by Mark Hoffman)

In this handout image provided by Sydney Tower Eye, a visitor scans the skyline and harbour of Sydney from a viewing platform at the Sydney Tower Eye, on December 16, 2011 in Sydney, Australia. Sydney is suffering from its coldest start to summer since 1960. (Photo by Eugene Tan/Hausmann Communications via Getty Images)

A villa privately built on the rooftop of a residential building in downtown Beijing has prompted complaints from neighbours living below. Professor Zhang, the villa owner, has been instructed to tear down the illegal building, according to the property managers. (Photo by Mark Ralston/AFP Photo)