U.S. Air Force pilots with the Thunderbirds perform the calypso pass maneuver in F-16 Fighting Falcon aircraft during a practice session prior to the Gunfighter Skies air show at Mountain Home Air Force Base, Idaho, September 19 and released September 24, 2014. (Photo by Tech. Sgt. Manuel J. Martinez/Reuters/US Air Force)

Roman Amoyan of Armenia, bottom, and Elman Mukhtarov of Azerbaijan compete in the the Men's wrestling, 59kg Greco-Roman Bronze Medal event at the 2015 European Games in Baku, Azerbaijan, Saturday, June 13, 2015. (AP Photo/Dmitry Lovetsky)

A group of young men use a selfie stick to take a picture of themselves in shallow waters known as the first cataract of the River Nile outside Khartoum, Sudan, May 22, 2015. In Sudan, which faces insurgences in the western region of Darfur and along its border with breakaway South Sudan, as well as double-digit inflation and high unemployment, life goes on for young people in the capital Khartoum. (Photo by Mohamed Nureldin Abdallah/Reuters)

A mahout watches the Thai animation movie Kan Kluay with his elephant in Ayuthaya province, about 80km (49 miles) north of Bangkok June 5, 2006. The movie tells the story of a young Thai wild elephant who, while looking for his father, becomes the war elephant of the Thai King fighting against Burma and restored Thailand's ancient Ayuthaya empire that existed about 400 years ago. (Photo by Sukree Sukplang/Reuters)

A woman spends her time outdoors to observe the ancient festival of Sizdeh Bedar, an annual public picnic day on the 13th day of the Iranian new year, at the Tochal mountainous area northern Tehran, Iran, Sunday, April, 2, 2017. Sizdeh Bedar, which comes from the Farsi words for “thirteen” and “day out”, is a legacy from Iran's pre-Islamic past that hard-liners in the Islamic Republic never managed to erase from calendars. (Photo by Ebrahim Noroozi/AP Photo)

British model Jourdan Dunn arrives for the premiere of “The Killing of a Sacred Deer” during the 70th annual Cannes Film Festival, in Cannes, France, 22 May 2017. The movie is presented in the Official Competition of the festival which runs from 17 to 28 May. Dress by Elie Saab Haute Couture. (Photo by Julien Warnand/EPA)

A mahout bathes his elephant in the river Sabarmati on a hot summer day in Ahmedabad, India May 21, 2017. (Photo by Amit Dave/Reuters)