A participant in the traditional dance of Los Historiantes poses for a picture prior to performing in the festivity held in the honour of Saint James, in Santiago Nonualco July 22, 2015. The traditional dance was brought to Latin America by the Spanish, and participants each dramatise an episode of the battles between the Christians and the Moors that took place on the Iberian Peninsula about eight centuries ago, according to the dancers. (Photo by Jose Cabezas/Reuters)

Vivian Odhiambo, 24, frys samosas in the trading centre of Kogelo, west of Kenya's capital Nairobi, July 14, 2015. Odhiambo said, “Obama is our hero and we wait to welcome him back home again. We in Kogelo have witnessed general growth and we are proud of being associated with the Obamas”, she added. As U.S. President Barack Obama visits Kenya, a personal connection to his father's birthplace of Kogelo dominates a trip that Kenyans view as a native son returning home. Residents from a herdsman to a housewife share their views on what Obama has achieved and what they would like to see next. (Photo by Thomas Mukoya/Reuters)

Piper Hoppe, 10, from Minnetonka, Minnesota, holds a sign at the doorway of River Bluff Dental clinic in protest against the killing of a famous lion in Zimbabwe, in Bloomington, Minnesota July 29, 2015. A Zimbabwean court on Wednesday charged a professional local hunter Theo Bronkhorst with failing to prevent an American from unlawfully killing “Cecil”, the southern African country's best-known lion. The American, Walter James Palmer, a Minnesota dentist who paid $50,000 to kill the lion, has left Zimbabwe. He says he did kill the animal but believed the hunt was legal and that the necessary permits had been issued. (Photo by Eric Miller/Reuters)

Birds fly over the Atomic Bomb Dome in Hiroshima, western Japan July 29, 2015. On August 6, 1945, the U.S. dropped the atomic bomb on Hiroshima, killing about 140,000 by the end of the year in a city of 350,000 residents, in the world's first nuclear attack. Three days later, a second atomic bomb was dropped on Nagasaki. Influenced by the shadows scorched into outdoor surfaces by the heat of the blasts 70 years ago, Reuters photographer Issei Kato pays homage to survivors, residents and historic buildings in both cities in a personal project that captures the shadows of today. (Photo by Issei Kato/Reuters)

Damaged train coaches at the site of a train accident, 180 kilometers from Bhopal near Harda district of Mahdya Pradesh, India, 05 August 2015. At least 25 people died when two passenger trains derailed in central India after heavy monsoon rains flooded railway tracks, officials said. Ten coaches from the trains toppled while approaching a small bridge just before midnight. (Photo by Sanjeev Gupta/EPA)

Militants loyal to Yemen's exiled government ride on the back of a pick-up truck in the country's central city of Taiz August 19, 2015. Militia forces loyal to Yemen's exiled government fought their way deep into the central city of Taiz this week, local officials said, largely pushing out Houthi militiamen from the country's third largest city. (Photo by Reuters/Stringer)

Photographer Carlos Barria holds a print of a photograph he took in 2005, as he matches it up at the same location 10 years on, in Lafitte, south of New Orleans, United States, August 16, 2015. The print shows Tyler Teal cleaning up his home, September 14, 2005, after Hurricane Katrina struck. In 2005, Hurricane Katrina triggered floods that inundated New Orleans and killed more than 1,500 people as storm waters overwhelmed levees and broke through floodwalls. (Photo by Carlos Barria/Reuters)

A competitor tries to swipe away some grease as he slips off the “gostra”, a pole covered in grease, during the celebrations for the religious feast of St Julian, patron of the town of St Julian's, outside Valletta August 30, 2015. In the traditional “gostra”, a game stretching back to the Middle Ages, young men, women and children have to make their way to the top of a pole and try to uproot one of the flags to win prizes. Photo by Darrin Zammit Lupi/Reuters)