Rebel fighters fire towards positions of regime forces in Ramussa on the southwestern edges of Syria's northern city of Aleppo on August 6, 2016. Syrian rebels said they have broken a three-week government siege of second city Aleppo, turning the tables on Russian-backed regime forces who are now on the defensive. (Photo by Fadi Al-Halabi/AFP Photo)

Thomas jumps into the water from a spring board at a public swimming pool in Mengen, Germany, 28 August 2016. (Photo by Thomas Warnack/EPA)

In this Monday, March 18, 2019 photo, a street artist performs in Caracas, Venezuela. Venezuelans are facing a severe economic and political crisis as President Nicolas Maduro has remained in power despite heavy pressure from the United States and other countries arrayed against him, managing to retain the loyalty of most of Venezuela's military leaders. (Photo by Natacha Pisarenko/AP Photo)

A portrait of French WWI soldier Edouard Marius Ivaldi is displayed on a tablet, in this illustration picture, alongside his battlefield grave memorial, a wooden cross with a battlefield helmet in Champagne, eastern France, November 3, 2015. (Photo by Charles Platiau/Reuters)

A young man, who says he is part of a local criminal gang, poses for a picture holding a gun in the neighbourhood of Korogcho in Nairobi, Kenya, March 19, 2015. Around 2 million people live in the shantytowns packed in around Kenya's capital. Crime is high amid chronic unemployment levels, while basic services and sanitation are scarce. Residents try to make the best of things, eking out a living and picking up work where they can. (Photo by Siegfried Modola/Reuters)

An Army Sikorsky VH-34s Choctaw helicopter once used to transport President Dwight D. Eisenhower sits in a field at the 309th Aerospace Maintenance and Regeneration Group boneyard Thursday, May 14, 2015 at Davis-Monthan Air Force Base in Tucson, Ariz. President Eisenhower became the first chief executive to be transported by helicopter. Presidents Eisenhower and John F. Kennedy were transported in VH-34 helicopters and VH-34's served as “Army One” from 1958 through 1963. (Photo by Matt York/AP Photo)

A partially burned American flag lies on the street near the spot where Michael Brown was killed before an event to mark the one year anniversary of his killing in Ferguson, Missouri August 9, 2015. (Photo by Rick Wilking/Reuters)

A devotee dressed as Hindu Lord Shiva waits to participate in a parade during “Kumbh Mela” or the Pitcher Festival in Trimbakeshwar, India, August 18, 2015. The Kumbh Mela takes place four times every 12 years at four different river bank locations in India. (Photo by Danish Siddiqui/Reuters)