Street vendors hold campaign posters for presidential candidate Patrice Talon ahead of the second round of Benin's presidential election on Sunday in Cotonou, Benin, March 18, 2016. (Photo by Charles Placide Tossou/Reuters)

The British Breitling Wingwalkers, Danielle Hughes and Emily Guilding, soar above the Palm Jumeirah in Dubai at 1,500 feet (460 meters) in excess of 100mp/h, ahead of their Dubai debut performance at the 2014 UIM Skydive Dubai XCAT World Powerboating Series, on Saturday, 13th December 2014. The British team is the only aerobatic formation display team who employ full time wingwalkers and fly their two Breitling-liveried 1930's Boeing Stearman bi-planes at Air Shows and major sporting events around the world. (Photo by Katsuhiko Tokunaga/Breitling via AP Images)

This picture taken on January 25, 2015 shows a participant taking part in an ice water challenge in Zhangjiajie, central China's Hunan province. Participants were required to stay in an ice pond, holding an ice block while eating ice-cream with an electric fan blowing at them. (Photo by AFP Photo/Stringer)

A woman carries a piglet as she runs on ice during a running challenge in Changsha, Hunan province February 8, 2015. A total of 20 people participated in the challenge requiring them to choose a pig ranging between 15 kg and 115 kg in weight, and carrying it while running on a 20.15-metre-long ice track. The participants that complete the challenge will be rewarded with the pig they carried, local media reported. (Photo by Darwin Zhou/Reuters)

A devotee takes a holy bath at the Balaju Baise Dhara (22 water spouts) during the Baishak Asnan festival in Kathmandu April 4, 2015. Devotees believe that the water from these stone spouts, which is collected from the catchment area of the Nagarjun forest behind the spouts, will cure pains and skin diseases. (Photo by Navesh Chitrakar/Reuters)

Cheng Chen (R), a 27-year-old worker at a state-owned enterprise, poses for a photograph with his nephew who is wearing his home-made Iron Man armour, in Xuzhou, Jiangsu province April 13, 2015. It cost Cheng about 500 yuan ($81 USD) to make the armour, which weighs about 4 kilograms, with plastic boards and LED lights, local media reported. (Photo by Reuters/Stringer)

Udomsak Ratanotayo, left, and Suttinan Boonsomkiat wear storm trooper costumes while donating blood at the Thai Red Cross in Bangkok, Thailand on Monday, April 28, 2014. Thai Star Wars fans will donate blood and give toys at an orphanage as part of a promotional campaign. (Photo by Sakchai Lalit/AP Photo)

Indian commuters travel in a local train in Kolkata, India, Tuesday, February 26, 2013. Indian Railway Minister Pawan Kumar Bansal is presenting the country's rail budget for next fiscal year in the parliament Tuesday, Feb. 26, 2013. Indian railway network is one of the world's largest, with some 14 million passengers daily and some 64,000 kilometers (40,000 miles) of railway track cut through some of the most densely populated cities. (Photo by Bikas Das/AP Photo)