Members of the Guard of Honor of the Presidential Regiment from Russia perform during the “Spasskaya Tower” international military music festival at Moscow's Red Square, Russia, September 10, 2015. The festival runs until 13 Sepember. (Photo by Maxim Shemetov/Reuters)

A displaced Yemeni woman from Hodeida fills water containers at a make-shift camp in a village in the northern district of Abs in the country's Hajjah province, on May 9, 2019. The Yemeni conflict has triggered what the United Nations describes as the world's worst humanitarian crisis, with 3.3 million people still displaced and 24.1 million in need of aid. (Photo by Essa Ahmed/AFP Photo)

Prime Minister Theresa May meets Russian President Vladimir Putin during the G20 summit in Osaka, Japan on June 28, 2019. (Photo by Stefan Rousseau/PA Images via Getty Images)

Military officers look at an AR-10 sniper rifle at LAAD, the biggest military industry expo in Latin America in Sao Paulo, Brazil April 10, 2018. (Photo by Nacho Doce/Reuters)

In this photograph taken on June 11, 2018, Chinese artists performs during a Indo-China cultural exchange program in Kolkata, West Bengal, India. (Photo by Dibyangshu Sarkar/AFP Photo)

Cambridge students the morning after the Trinity and Jesus college May Balls in Cambridge, United Kingdom on June 19, 2018. Students at Cambridge University celebrate the end of the academic year with the May Balls. (Photo by South West News Service)

Participants gather during a traditional hunting contest, involving tamed golden eagles and hawks, in Almaty, Kazakhstan on December 1, 2018. (Photo by Pavel Mikheyev/Reuters)

Masked guests attend the “Grand Bal Christian Dior” during the Haute Couture Spring-Summer 2018 fashion collection presented in Paris, Monday, January 22, 2018. (Photo by Kamil Zihnioglu/AP Photo)