Professional wrestler “p*ssy Willow” overpowers client Wilfred during their BDSM wrestling session at The Submission Room session wrestling and BDSM gym in Seven Sisters, on December 12, 2016 in London, England. (Photo by Susannah Ireland/Barcroft Images)

Indonesian tourists take a selfie as Mount Bromo spews volcanic material and ash into the air during an eruption in Probolinggo, East Java, Indonesia, 31 December 2015. Indonesia's Mount Bromo is on the second highest alert level as its activity has increased in the last two months. (Photo by Fully Handoko/EPA)

Women pose for a picture at Havana city, Cuba, March 17, 2016. Obama arrives in Havana on Sunday for a historic visit that seals a rapprochement he and Cuban President Raul Castro agreed in December 2014 after 18 months of secret negotiations. (Photo by Ivan Alvarado/Reuters)

A charity runner dressed as Father Christmas steps out of a portable toilet ahead of the “Santa Run” charity fun run in Stockholm on December 10, 2017. Hundreds of participants dressed in Santa suits and wearing white beards ran through the streets of the old town in Stockholm in an all charity run. (Photo by Jonathan Nackstrand/AFP Photo)

In this picture taken on December 13, 2017, a woman commutes on a street on a cold day in Baoding. As temperatures dipped below freezing in a northern Chinese village, a group of parka-clad women tried to stay warm as they played mahjong around a small gas stove in a grocery store. (Photo by Fred Dufour/AFP Photo)

In this photograph taken on December 8, 2017, Indian child Samarth Bangari, 2, plays with langur monkeys at his home in Allapur in India' s southwest Karnataka state, 250 miles from Bangalore. He is still too young to talk, but a 2- year- old Indian boy has become a subject of local intrigue after befriending a gang of langur monkeys. (Photo by Manjunath Kiran/AFP Photo)

“Left behind” children Luo Hongni, 11 (L) and brother Luo Gan,10, carry flowers to be used as feed while doing chores in the fields on December 18, 2016 in Anshun, China. Like millions of Chinese children, the four Luo siblings are being raised by their grandparents in rural China as their parents left to find work in urban areas. (Photo by Kevin Frayer/Getty Images)

A woman takes pictures with her mobile phone at a building, which is made by half of a replica of the Qinian Hall of the Temple of the Heaven (R) and half of a western building, at a studio for productions of films and television shows on the outskirts of Shijiazhuang, Hebei province, China, December 3, 2015. (Photo by Reuters/Stringer)