A Chinese girl touches the gun of a relievo featuring Chinese soldiers fighting with Japanese troops during World War II at an exhibition at the Anti-Japan War Museum to mark the 60th Anniversary of the Victory of the Chinese People's War of Resistance Against Japan on August 18, 2005 in Beijing, China. (Photo by Cancan Chu/Getty Images)

A military instructor helps a boy to shoot a rifle with blanks at a weapon exhibition during a military show in St.Petersburg, Russia, Sunday, January 17, 2016. (Photo by Dmitry Lovetsky/AP Photo)

Serena Williams of the U.S. serves during her first round match against Italy's Camila Giorgi at the Australian Open tennis tournament at Melbourne Park, Australia, January 18, 2016. (Photo by Jason O'Brien/Reuters)

A woman looks at a swimmer getting herself warm after the annual Christmas winter swimming competition in the Vltava river in Prague December 26, 2014. (Photo by David W. Cerny/Reuters)

A Pakistani farmer guides his bulls as he competes in a traditional bull race in Khunda village in the northwestern district of Attock, some 80 kilometers from Islamabad on January 3, 2015. Tens of thousands of people gather whenever there is a bull race held in Pakistan which are usually the highlight of festivals organized in rural areas of the Asian country, and attract lots of spectators due to their thrilling nature. The traditional competition attracts landlords and farmers from all around the province where the race is held, and they all bring their fastest and strongest bulls in hopes of gaining a reputation. (Photo by Aamir Qureshi/AFP Photo)

In this April 20, 2017 photo, a woman is aided by fellow demonstrators after falling, overcome by tear gas, during anti-government protests in Caracas, Venezuela. Tens of thousands of protesters asking for the resignation of President Nicolas Maduro flooded the streets again, one day after three people were killed and hundreds arrested in the biggest anti-government demonstrations in years. (Photo by Ariana Cubillos/AP Photo)

US President George W. Bush (R) and Russian President Vladimir Putin wave as the two presidents go for a ride in Putin's 1956 Volga before dinner 08 May 2005 at the his residence outside of Moscow. Bush hailed Russia's “bravery and sacrifice” in defeating Nazism, as he met Putin ahead of ceremonies marking the 60th anniversary of the end of World War II. Bush, who the previous day criticized the decades-long Soviet occupation of central Europe, said he was looking forward to the 09 May ceremony on Moscow's Red Square, to be attended by over 50 national leaders. (Photo by Tim Sloan/AFP Photo)