A model wears a floral head dress as she promotes a chain of garden centres at the Royal Horticultural Soceity's Chelsea Flower Show in London, Britain, May 18, 2015. (Photo by Toby Melville/Reuters)

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)

Riot police stand guard behind a fire as refinery workers hold a blockade of the oil depot of Douchy-Les-Mines to protest against the government's proposed labour reforms, on May 25, 2016. Refinery workers stepped up strikes that threaten to paralyse France weeks ahead of the Euro 2016 tournament as the government moved to break their blockades, escalating a three-month tug-of-war over labour reforms. (Photo by François L.O./AFP Photo)

Heralds ride on horse-back through the streets of Moscow proclaiming the forthcoming coronation of Tsar Nicholas II, 1896. P.S. All pictures are presented in high resolution.

A boy walks with toy guns as people ride an APC during a military show at the Finnish Gulf coast in St.Petersburg, Russia, Saturday, September 5, 2015. (Photo by Dmitry Lovetsky/AP Photo)

An Omani woman prepares for a traditional dance during a ceremony attended by Britain's Prince Charles and his wife, Camilla, Duchess of Cornwall in Muscat, Oman, Saturday, November 5, 2016. The royal couple have started a three-nation royal tour of the Gulf in Oman. (Photo by Kamran Jebreili/AP Photo)

Members of Chinese Shaolin Temple Warrior Monks perform martial arts during the “Cultures of China, Festival of Spring” Gala in Toronto, Canada, on February 27, 2016. (Photo by Zou Zheng/Xinhua/Sipa USA)

A dressed up Oakland Raiders fan poses for photos as she arrives at Azteca stadium in Mexico City, Monday, November 21, 2016. The Oakland Raiders face the Houston Texans at a sold out Azteca stadium. (Photo by Dario Lopez-Mills/AP Photo)