Participants cross cold and muddy waters during the Strong Race competition near Tukums May 4, 2014. About 6500 people competed in this extreme running race, which includes cross-country running, elements of agility and power discipline. (Photo by Ints Kalnins/Reuters)

Revellers take part in the Holi Party Festival at the Niemeyer Center in Aviles, northern Spain, August 29, 2015. The event is inspired by the Hindu Holi spring festival of colour celebrated mostly in India but has recently spread to other countries. (Photo by Eloy Alonso/Reuters)

This handout picture taken on December 13, 2016 and released on December 14, 2016 by the Tiergarten Schoenbrunn zoo in Vienna, Austria, shows a baby sloth eating some salad as it hangs on it's mother's belly in their enclosure. The baby was born already on November 18, 2016, but according to the zoo it could be picured for the first time only now as it usually hides in it's mother's soft coat. (Photo by Daniel Zupanc/AFP Photo)

A local youth, front right, scares pupils on a street as he takes part in a ceremony to exorcize evil spirits and pray for rain amid the rice planting season at Pring Ka-ek village, northwest of Phnom Penh, Cambodia, Friday, May 22, 2015. Cambodia is a country which heavily relies on agriculture as over 80 percent of its 14 million people are farmers, growing rice as their main crop. (Photo by Heng Sinith/AP Photo)

A woman attends a boxing class at Princess Women's Boxing Club in Shanghai December 3, 2014. Women have boxed as long as the sport has existed but for years they were relegated out of national and international competitions in many countries around the world. Female boxers entered the ring in an exhibition match at the 1904 Olympic Games, but it was more than a century later when they were given the green light to make their Olympic debut in London in 2012. (Photo by Carlos Barria/Reuters)

A women attends a class at a driving school in Kabul August 17, 2014. Kabul is one of the world's fastest growing cities and its streets are increasingly blocked by cars and buses. In the city's private driving schools, students pay a $60 fee for a 45-day course, which includes oral and practical driving tests at the country's Traffic Department. Some of the women who have signed up say learning to drive is a way to escape unwanted gazes and physical harassment on the cramped, crowded minibuses that are often the only method of urban public transport. (Photo by Mohammad Ismail/Reuters)

A Colombian flower grower selects a rose for a bouquet ahead of Valentine's Day in Subachoque, February 2, 2015. Colombia is the world's second-largest flower exporter behind the Netherlands. The Andean country exports around 500 million flowers to the U.S. for Valentine's Day, according to the Colombia Flower Growers Association. (Photo by John Vizcaino/Reuters)

A girl walks down the runway during a class at a modelling academy in Caracas, Venezuela, on September 20, 2014. Venezuela's famed models and aspiring beauty queens are struggling to doll themselves up. In a country that glorifies voluptuous women and opulent beauty pageants, even basics like deodorant are now at times tricky to find as strict currency controls have led to a scarcity of dollars for imported goods. (Photo by Carlos Garcia Rawlins/Reuters)