Su Daocheng rides his home-made mechanical horse vehicle on a street in Shiyan, Hubei province January 18, 2015. Su spent 2 months making this 1.5 metre high and 2 metre long horse, which weighed 250 kilograms with 4 legs and 2 supportive wheels, local media reported. (Photo by Reuters/Stringer)

A Yemeni soldier, pictured through a vehicle's windscreen, which was damaged by a bullet, gestures out of the window, in Marib, Yemen October 15, 2015. Marib is a city that is heavily armed even by the standards of Yemen, where the ready availability of weapons helped start civil war and is now preventing anyone coming out on top. Yemenis often say there are three guns for every person, a boast that has become an urgent concern in a country where the United Nations says the humanitarian situation is "critical". (Photo by Angus McDowall/Reuters)

In this Tuesday, March 12, 2019 photo, a visitor takes part in an immersive experience showing visitors how dogs see from inside the head of a dog at the California Science Center in Los Angeles. A new exhibit at a Los Angeles museum examines the relationship between dogs and humans and explores why the two species seem to think so much alike and get along so well. “Dogs! A Science Tail” opens Saturday, March 16, 2019, at the California Science Center. (Photo by Richard Vogel/AP Photo)

A displaced Yemeni woman from Hodeida fills water containers at a make-shift camp in a village in the northern district of Abs in the country's Hajjah province, on May 9, 2019. The Yemeni conflict has triggered what the United Nations describes as the world's worst humanitarian crisis, with 3.3 million people still displaced and 24.1 million in need of aid. (Photo by Essa Ahmed/AFP Photo)

Balinese girls in traditional costumes gather during a parade for this year's last sundown in Bali island, Indonesia Thursday, December 31, 2015. (Photo by Firdia Lisnawati/AP Photo)

Syrian President Bashar Al Assad watches as Pope John Paul II boards his plane at Damascus airport May 8, 2001 at the end of the Pontiff's four-day visit to Syria.

Jean-Pierre Giagnoli walks through a crowded area of vendors hawking cat related goods at CatCon LA in Los Angeles, on Sunday, June 26, 2016. (Photo by Richard Vogel/AP Photo)

Female members of police commando march during a ceremony on International Women's Day, at the police headquarters in Islamabad, Pakistan March 8, 2018. (Photo by Faisal Mahmood/Reuters)