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)

Nyibol Lual, 13 years old, helps her family to prepare the land for cultivation on May 31, 2017, in Panthau, Northern Bahr al Ghazal, South Sudan. The family has a small land where they cultivate sorghum. An estimated 63 per cent of the population in Northern Bahr al Ghazal is experiencing severe food insecurity, according to the latest Integrated Food Security Phase Classification (IPC) report. The situation is particularly bad in Aweil West and Aweil South counties, where the exhaustion of household food stocks and growing dependence on financially inaccessible markets have left the population facing Emergency levels of food insecurity. (Photo by Albert Gonzalez Farran/AFP Photo)

A Monster Jam truck performs a back flip during the first-ever monster truck event in Beijing's iconic “Bird's Nest” National Stadium on Saturday, July 29, 2017. (Photo by Ng Han Guan/AP Photo)

A flood affected boy on a makeshift banana raft collects biscuit packets distributed by a government official from a boat in Pokoria village, east of Gauhati, north eastern Assam state, India, Monday, August 14, 2017. Heavy monsoon rains have unleashed landslides and floods that killed dozens of people in recent days and displaced millions more across northern India, southern Nepal and Bangladesh. (Photo by Anupam Nath/AP Photo)

Somalis remove the body of a man killed in a blast in the capital Mogadishu, Somalia Saturday, October 14, 2017. A huge explosion from a truck bomb has killed at least 20 people in Somalia's capital, police said Saturday, as shaken residents called it the most powerful blast they'd heard in years. (Photo by Farah Abdi Warsameh/AP Photo)

Enthusiasts gathered at Cad East in Snowdonia National Park, England to take pictures of F-15 Eagle fighters as they completed the Mach Loop, November 2017. (Photo by Caters News Agency)

Filipino children play as they are doing caroling activities on the street near an airport, days before Christmas in Manila, Philippines, 20 December 2017. Filipinos celebrate the longest Christmas in the world which starts as early as September every year. (Photo by Francis R. Malasig/EPA/EFE)

A boy plays with pelicans in Yoff, commune of Dakar, Senegal March 14, 2018. (Photo by Zohra Bensemra/Reuters)