A man sleeps on a wheelbarrow outside a closed shop at a market during the first day of a ceasefire in Yemen's capital Sanaa April 11, 2016. (Photo by Khaled Abdullah/Reuters)

A student shouts slogans against Venezuelan President Nicola Maduro during a protest on the main highway in Caracas on March 30, 2017. Venezuela' s Supreme Court took over legislative powers Wednesday from the opposition- majority National Assembly, whose speaker accused leftist President Nicolas Maduro of staging a “coup”. (Photo by Juan Barreto/AFP Photo)

An Egyptian actress working at the Pharaonic Village simulates ancient agriculture scenes during a show marking Sham el-Nessim, or “smelling the breeze”, in Giza, Egypt, Monday, April 13, 2015. The holiday signifies the arrival of Spring, a uniquely Egyptian tradition practiced since the days of the Pharaohs. (Photo by Amr Nabil/AP Photo)

An Indian nomadic Gujjar girl hangs on to a horse cart after collecting bricks from debris on the outskirts of Jammu, India, Tuesday, March 7, 2017. The Gujjar tribal communities are considered by some to be economically and socially backward and the lack of care by the state government has led to resentment amongst the community. The tribe moves to the plains from the hills to escape the cold winters. (Photo by Channi Anand/AP Photo)

Suited volunteers in bowler hats stand in the surf holding umbrellas aloft at sunrise at Bondi Beach on June 27, 2010 in Sydney, Australia. The human installation is the latest in a series of “surreal human sculptures” by artist Andrew Baines (Photo by Brendon Thorne/Getty Images)

A worker stands under covered elephant statues at the Ambedkar Park on January 11, 2012 in Noida, Uttar Pradesh, India. India's Election Commission has ordered the covering up of statues, the symbol of the Bahujan Samaj Party, ahead of next month's elections in the state of Uttar Pradesh. (Photo by Daniel Berehulak /Getty Images)

Two workers shovel mud from the river as they look for gold on March 25, 2014 in Lampang, Thailand. Thai villagers from Wang Nuea, North of Thailand, look for gold in the river every year during the drought season. They are able to make an average around USD 15 per day, however two years ago they reached USD 200 in one day due to the river level dropping so much. The workers begin to search for gold at 10 AM and work until sunset, often working second jobs in the day in order to survive. (Photo by Borja Sanchez-Trillo/Getty Images)

Three-years-old dog Hope uses a wheelchair to run next to its owner Regine Grosinger in Vienna September 3, 2014. Hope was found with cut-off back legs in the countryside and brought to an animal asylum when it was four-month-old. Grosinger took the dog home two months later and had a wheelchair manufactured for it. (Photo by Heinz-Peter Bader/Reuters)