Visitors hold ice blocks to cool themselves in hot weather at a water park on June 23, 2016 in Chongqing, China. Citizens and visitors escaped high temperature at a water park in Yangren Jie (also known as Foreigner Street), Nan'an District of south China's Chongqing. (Photo by VCG/VCG via Getty Images)

A homeless girl asks for alms outside a coffee shop in Mumbai, India, June 24, 2016. (Photo by Danish Siddiqui/Reuters)

In this May 14, 2016 photo, children wearing their school backpacks climb on a cliff using a bamboo ladder on their way home from school in Zhaojue county, southwest China's Sichuan province. A village in China's mountainous west where schoolchildren must climb an 800-meter (2,625-foot)-high bamboo ladder secured to a sheer cliff face may get a set of steel stairs to improve it's safety. (Photo by Chinatopix via AP Photo)

In this August 28, 1963 file photo, the top of the Washington Monument and part of a U.S. flag are reflected in the sunglasses of Austin Clinton Brown, 9, of Gainesville, Ga., as he poses at the Capitol where he joins others in the March on Washington. (Photo by AFP Photo)

An East German civilian (L) shows an East German customs officer the contents of his Trabant (auto) at checkpoint Potsdamer Platz in East Berlin in this November 24, 1989 file picture, as East Germany enforcing stringent customs controls to avoid smuggling. (Photo by Reuters)

A boat, center, is surrounded by Japan Cost Guard's patrol boats after some activists descended from the boat on Uotsuri Island, one of the islands of Senkaku in Japanese and Diaoyu in Chinese, in East China Sea Wednesday, Aug. 15, 2012. Regional tensions flared on the emotional anniversary of Japan's World War II surrender as activists from China and South Korea used Wednesday's occasion to press rival territorial claims, prompting 14 arrests by Japanese authorities. The 14 people had traveled by boat from Hong Kong to the disputed islands controlled by Japan but also claimed by China and Taiwan. (Photo by Yomiuri Shimbun/Masataka Morita/AP Photo)

Residents watch volcanic smoking and ashes rising from Mount Sinabung during an eruption in Karo, North Sumatra, Indonesia, February 24, 2016. Authorities have repeatedly called on local residents to remain patient in dealing with the impact of Sinabung's eruptions, which some experts have predicted will continue for five more years. (Photo by Xinhua/Barcroft Media)

Revelers celebrate during fireworks marking the start of the New Year on Copacabana beach on January 1, 2017 in Rio de Janeiro, Brazil. (Photo by Mario Tama/Getty Images)