Iranian mourners cover themselves with mud during Ashoura, marking the death anniversary of Imam Hussein, the grandson of Islam's Prophet Muhammad, at the city of Bijar, west of the capital Tehran, Iran, Thursday, November 14, 2013. Hussein, one of Shiite Islam's most beloved saints, was killed in a 7th century battle at Karbala, Iraq. (Photo by Ebrahim Noroozi/AP Photo)

American Yoga teacher Dashama poses on a Yoga-board during a preview of the 46th International Boat Fair in Duesseldorf January 16, 2015. The BOOT 2015 watersports fair, with more than 1,600 international exhibitors will run in Duesseldorf from January 17 to January 25. (Photo by Ina Fassbender/Reuters)

This picture taken on February 16, 2017 in Fangshan village in China's coastal province Fujians, shows a villager performing the “eating flowers” ritual. Villagers in eastern China have a unique way of washing away the taint of evil spirits – by bathing in a shower of scorching sparks. (Photo by Johannes Eisele/AFP Photo)

A combination photo shows various popular street foods under $6 from various hawker food stalls and eateries in Singapore, taken between July 28 to 31, 2016. Top row (L to R) bak chor mee, soya sauce chicken; Middle row (L to R) laksa, hokkien mee, nasi lemak, ice kachang; Bottom row (L to R) rojak, roti prata and satay. (Photo by Edgar Su/Reuters)

A couple stands next to a poster depicting Dutch politician Geert Wilders and Russian President Vladimir Putin kissing, at a metro station in Amsterdam April 3, 2016. (Photo by Cris Toala Olivares/Reuters)

Contestants of a tourism beauty pageant balance eggs on their collarbones as they cruise along the Yellow River in Jiyuan, Henan province, China, June 22, 2015. The contestants believe that if they are slim enough, their collarbones will allow them to balance the eggs securely on their bodies. (Photo by Reuters/Stringer)

A Tibetan mastiff dog is displayed for sale at a mastiff show in Baoding, Hebei province, south of Beijing on March 9, 2013. Fetching prices up to around 750,000 USD, mastiffs have become a prized status-symbol amongst China's wealthy, with rich buyers across the country sending prices skyrocketing. Owners say the mastiffs, descendents of dogs used for hunting by nomadic tribes in central Asia and Tibet are fiercely loyal and protective. Breeders still travel to the Himalayan plateau to collect young puppies, although many are unable to adjust to the low altitudes and die during the journey. (Photo by Ed Jones/AFP Photo)

Spanish actor Antonio Banderas embraces a robot used in the film Automata during a photocall on the third day of the 62nd San Sebastian Film Festival, September 21, 2014. Banderas stars in and produced the science fiction film, which is part of the festival's official section. (Photo by Vincent West/Reuters)