Policemen detain topless activists of women's rights group Femen, who stage a performance during a protest against Ukrainian President Petro Poroshenko and the government while marking the Day of Dignity and Freedom near the presidential administration headquarters in Kiev, Ukraine November 21, 2017. (Photo by Valentyn Ogirenko/Reuters)

In this November 2, 2017 photo, Mathew Fulkerson and his wife Leigh Ann pose at their Subterra Airbnb located in a former underground missile silo base near Eskridge, Kan. It was designed to house a nuclear warhead six decades ago – but now, this Cold War silo is the perfect spot for a mini break at just $133 a night. (Photo by Thad Allton/The Topeka Capital-Journal via AP Photo)

Marie Lou looks out of the window of gypsy folklore wagon on May 24, 2016 in Staintes Maries de la Mere near Arles, France. Gypsies from all over Europe worship “Sara the Black”, their Saint and patroness, for one week. Sara's statue is situated in the crypt of the church. She wears a multicoloured dress and will carried by the gypsies to the sea at this afternoon. (Photo by Thomas Lohnes/Getty Images)

Models of the “Altyr” fashion theatre, dressed in Khakas national costumes, get over a wooden fence during a photo session, as a part of the rehearsal for the Tun-Pairam traditional holiday (The Holiday of the First Milk) celebration at a museum preserve outside Kazanovka village near Abakan in the Republic of Khakassia, Russia, May 28, 2016. (Photo by Ilya Naymushin/Reuters)

A technician holds a recently 3D printed replica of Darth Vader's melted helmet from “Star Wars: The Force Awakens”, in the Propshop headquarters at Pinewood Studios near London, Britain May 25, 2016. Propshop headquarters at Pinewood Studios is making limited edition replicas of Star Wars props. (Photo by Peter Nicholls/Reuters)

Participants dressed as characters such as elves, dwarves, goblins and orcs from the J.R.R. Tolkien's novel “The Hobbit” re-enact the “Battle of Five Armies” in a forest near the town of Doksy, Czech Republic, June 4, 2016. Several hundred people arrived in the forest to re-enact the famous battle from Tolkien's novel that was published for the first time in 1937. (Photo by David W. Cerny/Reuters)

A view of the scene of a train accident after two commuter trains collided head-on near the town of Andria, in the southern region of Puglia, killing several people, Tuesday, July 12, 2016. (Photo by Luca Turi/ANSA via AP Photo)

Turkana tribesmen walk with guns in order to protect their cattle from rival Pokot and Sambur tribesmen near Baragoy, Kenya February 14, 2017. Cattle rustling and competition for grazing have long troubled northern Kenya, but severe drought and political rivalries ahead of the elections have exacerbated the situation between ethnic tribes. (Photo by Goran Tomasevic/Reuters)