A girl walks in front of a graffiti painted on the wall of a house located inside the 15th-century complex built by Mameluk Sultan al-Ashraf Qaitbey, in Cairo's City of the Dead, Egypt February 13, 2017. (Photo by Amr Abdallah Dalsh/Reuters)

Attendees wear a cardboard “Facebox” at the 2017 South By Southwest (SXSW) Interactive Festival at the Austin Convention Center in Austin, Texas, U.S., on Monday, March 13, 2017. The SXSW Interactive Festival features a variety of tracks that allow attendees to explore what's next in the worlds of entertainment, culture, and technology. (Photo by David Paul Morris/Bloomberg)

Iraqi soldiers from 9th Armoured Division give drops of water to a dehydrated child rescued earlier by soldiers at the frontline, during the ongoing fighting between Iraqi forces and Islamic State militants near the Old City in western Mosul, Iraq June 13, 2017. (Photo by Erik De Castro/Reuters)

A model on a wheelchair presents creations by designer Takafumi Tsuruta from his Spring/Summer 2016 collection for his brand Tenbo, during Tokyo Fashion Week in Tokyo, Japan, October 13, 2015. (Photo by Yuya Shino/Reuters)

A man sleeps between tombstones in front of his single-room home on a hot night in the Cairo Necropolis, Egypt, October 13, 2015. In the sprawling Cairo Necropolis, known as the City of the Dead, life and death are side by side. Amid a housing crisis in Egypt, and with the population of greater Cairo estimated at about 20 million, people count themselves lucky to have a place to call home in the graveyards that date back hundreds of years. (Photo by Asmaa Waguih/Reuters)

Jennifer Oeser of Germany competes in the Women's Heptathlon Long Jump on Day 8 of the Rio 2016 Olympic Games at the Olympic Stadium on August 13, 2016 in Rio de Janeiro, Brazil. (Photo by Alexander Hassenstein/Getty Images)

Sikh devotees participate in the Baisakhi festival at Panja Sahib shrine in Hassan Abdel April 13, 2015. Hundreds of Indian Sikh pilgrims arrived into Pakistan to celebrate the Baisakhi festival with Pakistani Sikhs at the shrines of Panja Sahib and Nankana Sahib, the birth place of Sikh faith founder Guru Nanak Dev. (Photo by Caren Firouz/Reuters)

Cheng Chen (R), a 27-year-old worker at a state-owned enterprise, poses for a photograph with his nephew who is wearing his home-made Iron Man armour, in Xuzhou, Jiangsu province April 13, 2015. It cost Cheng about 500 yuan ($81 USD) to make the armour, which weighs about 4 kilograms, with plastic boards and LED lights, local media reported. (Photo by Reuters/Stringer)