Students hold their weapons before the swearing in ceremony for the military students, in Bucharest, Romania, Wednesday, October 25, 2017. The Romanian Army is proudly celebrating their Army Day and marking 100-years since the landmark battle of Marasesti, a key World War I battle in 1917 when Romanian and Russian soldiers defeated German troops, halting a German offensive. (Photo by Vadim Ghirda/AP Photo)

Armed women attend a rally to show support to the Houthi movement in Sanaa, Yemen January 13, 2018. (Photo by Khaled Abdullah/Reuters)

Ai (R) and Hamuka dressed in “Lolita fashion”, influenced by Victorian style, pose for a photographs at Harajuku shopping district in Tokyo, Japan March 15, 2018. (Photo by Kim Kyung-Hoon/Reuters)

Danila Shmelev, an artist from Moscow, Russia, works on a 3-D picture in Dubai, United Arab Emirates, Monday, February 27, 2017. Artists who focus on 3-D pictures have gathered in Dubai for the Dubai Canvas 3-D Art Festival, which runs from March 1 through March 7. (Photo by Jon Gambrell/AP Photo)

Lily Aldridge and Stella Maxwell arrive at the Daily Front Row's 3rd Annual Fashion Los Angeles Awards at the Sunset Tower Hotel on April 2, 2017 in West Hollywood, California. (Photo by Jon Kopaloff/FilmMagic)

A staff member sets up a ROBOTLEO robot at the Global Mobile Internet Conference (GMIC) 2017 in Beijing, China April 28, 2017. (Photo by Jason Lee/Reuters)

An Indian Hindu devotee celebrates Holi, the spring festival of colours, during a traditional gathering at a temple in Nandgaon village in Uttar Pradesh state on March 16, 2019. Holi, the popular Hindu spring festival of colours is observed in India at the end of the winter season on the last full moon of the lunar month. (Photo by Noemi Cassanelli/AFP Photo)

People walk passed sculptures by Chinese artist Minjun Yue on a street outside a museum in Beijing, China on July 5, 2018. (Photo by Nicolas Asfouri/AFP Photo)