Law enforcement officers clash with protesters, Wednesday, July 20, 2016, in Cleveland, during the third day of the Republican convention. (Photo by John Minchillo/AP Photo)

South Asian countries in terms of total contribution of travel and tourism to GDP. #6. Vietnam, Total GDP: USD 202.6 billion (2016). Contribution of Travel and Tourism to GDP: 9.1% . Here: A boat in the Thu Bon River, Hoi An, Vietnam. (Photo by Domingo Leiva/Getty Images)

Brave slackliners have been pictured walking the ropes above Rio de Janeiro, Brazil on August 15, 2016, with the half a mile drop showing the city in all its glory. The stunning shots show the daredevils tread across an eighty-two-foot-long high line on Pedra da Gvea mountain with an amazing sunrise illuminating the city landscape behind. (Photo by Rafael Moura/Caters News Agency)

In this September 10, 1977, file photo, from left, Hua Guofeng, Chinese Communist Party (CCP) chairman and Mao Zedong's immediate successor; Ye Jianying, CCP vice chairman and future ceremonial head of state; Deng Xiaoping, no formal titles at the time but soon to emerge as paramount leader during the reform era; Li Xiannian, CCP vice chairman and future president; Wang Dongxing, head of the leadership bodyguard unit who helped topple the Gang of Four, view the body of later Chinese leader Mao Zedong in Beijing. (Photo via AP Photo)

A woman looks at a handgun at the Glock booth at the Shooting Hunting and Outdoor Trade Show, Tuesday, January 19, 2016, in Las Vegas. The SHOT Show, the world's largest annual trade show for shooting, hunting and law enforcement professionals, runs through January 23 and is expected to feature 1,600 exhibitors showing off their latest products and services to more than 62,000 attendees. (Photo by John Locher/AP Photo)

Thai office workers walk past armed soldiers standing guard outside the Shinawatra Tower Two in Bangkok, Thailand, 20 May 2014. Thai army Chief Prayuth Chan-ocha early on 20 May 2014, declared martial law giving the military full control to prevent further protest-related violence in the country. The statement was issued about 3 am on 20 May (2000 GMT), according to local media reports. Prayuth has the authority to declare martial law without the consent of the government, which has had caretaker status since 09 December 2013. Thailand has been wracked by six months of non-stop protests seeking to topple the government. At least 25 people have died in political-related violence and more than 700 injured. (Photo by Narong Sangnak/EPA)

Yolanda Sutter dresses up her dog Star to show their support for Democratic presidential candidate Mike Bloomberg at the Viva Villa restaurant in San Antonio, Texas on January 11, 2020. Democratic presidential candidate Mike Bloomberg kicks off his Texas bus tour. (Photo by Mark Felix/AFP Photo)

A young Free Syrian Army fighter holds a rifle in Haresta neighbourhood of Damascus January 16, 2013. (Photo by Goran Tomasevic/Reuters)