Children watch their classmate pour cold water on herself under the watch of a fitness coach at a local kindergarten in Russia's Siberian city of Krasnoyarsk, March 11, 2015. The program, which also involves sports training and sauna usage, has been practiced by the kindergarten for more than 15 years as they believe it has health benefits and keeps the children fit. Children start pouring cold water on themselves outdoors after about three years of training and undergoing medical tests, and the kindergarten is the only one in the region that practices these exercises, according to employees. (Photo by Ilya Naymushin/Reuters)

In this March 3, 2015 photo, a group of California sea lions rest on a large bouy in the San Ignacio lagoon, in the Pacific Ocean, near Guerrero Negro, in Mexico's Baja California peninsula. (Photo by Dario Lopez-Mills/AP Photo)

A Hawker Hurricane Mk XIIa 5711 (G-HURI) fighter aircraft prepares to perform an aerobatic display at the IWM Duxford on October 18, 2012 in Duxford, England. The aeroplane, similar to those that defended British shores during the Battle of Britain in World War II, is due to be auctioned by Bonhams in their sale of “Collectors' Motor Cars and Automobilia” at Mercedes-Benz World Brooklands on December 3, 2012. The plane was built in 1942 and joined the Royal Canadian Air Force the following year, where it remained for the duration of the war, it is expected to fetch up to 17 million GBP. (Photo by Oli Scarff)

In this picture taken Thursday, April 14, 2016, a Syrian man carries a carpet as walk through a devastated part of the town of Palmyra as families load their belongings onto a bus in the central Homs province, Syria. Thousands of residents of this ancient town who fled Islamic State rule are returning briefly to check on their homes and salvage what they can – some carpets, blankets, a fridge or a few family mementos. There is no water or electricity in the town, and it will be at least few months before anyone can return to stay. (Photo by Hassan Ammar/AP Photo)

A World War II era P-51 Mustang fighter plane stands in front of a modern 747-8 freighter and a 757 passenger jet at The Boeing Company's centennial celebration in Renton, Washington, U.S. July 15, 2016. (Photo by Alwyn Scott/Reuters)

Steve Shirts, aka “Strike Pony”, left, gets a hug from Amber Snyder, aka “Ditsy Dots” in Baltimore, MD on July 8, 2016. Both are from Suburban Chicago. BronyCon is the world's largest My Pretty Pony convention. Featuring cosplay and fan events, the annual convention was held at the Baltimore Convention Center. (Photo by Andre Chung/The Washington Post)

Comedians and cast members from the Pleasance's 2016 programme bounce on yellow spacehoppers in costume at Calton Hill on August 15, 2016 in Edinburgh, Scotland. The Pleasance and Waverley Care are marking a twenty five years in partnership, it's a unique relationship that helps raise awareness and challenges the stigma that continues to be attached to HIV and Hepatitis C and has raised more than £375,000 so far. (Photo by Jeff J. Mitchell/Getty Images)

A boy takes a picture of a car crash in Shenzhen, Guangdong province, August 4, 2014. Two passengers were sent to hospital but no death was reported as a result of the accident, according to local media. (Photo by Reuters/Stringer)