A donkey carrying sacks of coal walks through the narrow tunnels of a coal mine, in Choa Saidan Shah in Punjab province April 29, 2014. Coal miners in Chao Saidan Shah use donkeys to transport coal from the depths of the mines to the surface. (Photo by Sara Farid/Reuters)

Caroline Wozniacki of Denmark serves in her match against Kaia Kanepi of Estonia during day four of the Toray Pan Pacific Open at Ariake Colosseum on September 28, 2011 in Tokyo, Japan. (Photo by Koji Watanabe/Getty Images)

Dancers from the British theater company Motionhouse perform a show with excavators entitled “Traction” on the Prado beach in Marseille, France, on May 10, 2013. (Photo by Boris Horvat/AFP Photo)

Two baby orangutans play with each other at the wildlife department in Kuala Lumpur, Malayasia, October 19, 2015. The Malaysian wildlife department in July seized two baby Sumatran orangutans, found in duffel bags, from traffickers who were attempting to sell them to buyers in Malaysia. According to local media, the orangutans will be returned to Medan, Indonesia on Tuesday. The illegal wildlife trade is estimated to be $8 billion a year worldwide, according to TRAFFIC, a wildlife trade monitoring network. (Photo by Olivia Harris/Reuters)

A picture made available on 21 July 2016 shows a visitor having a meal from a toilet bowl at “Jamban Cafe” (lit. Toilet Cafe) in Semarang, Central Java, Indonesia, 16 July 2016. The cafe was created by a sanitation expert for education purposes to stress the importance of using a dedicated toilet and keeping it clean to prevent disease. (Photo by EPA/Purwanto)

A young woman cools herself in a fountain in Budapest, Hungary July 6, 2015. Over the weekend, a heat wave has reached Hungary with temperatures topping 38 degrees Celsius (100.4 degrees Fahrenheit). (Photo by Laszlo Balogh/Reuters)

Onati Basque dancers go airborne as they perform Basque traditional dances while making their way to the front of Saint Mark's Catholic Church, Saturday, August 1, 2015, in Boise, Idaho. The annual Mass, conducted in English and Basque, was held at the church for the first time. (Photo by Kyle Green/Idaho Statesman via AP Photo)

Flying pigeons pass over Nepalese street vendors near the earthquake damaged UNESCO World Heritage Site, Durbar Square in Kathmandu on May 20, 2015. Nearly 8,500 people have now been confirmed dead in the disaster, which destroyed more than half a million homes and left huge numbers of people without shelter with just weeks to go until the monsoon rains. (Photo by Ishara S. Kodikara/AFP Photo)