A man poses in front of a portrait of late Chinese Chairman Mao Zedong during the opening of an exhibition of Mao related art in Beijing, China, September 8, 2016. (Photo by Thomas Peter/Reuters)

A tank rolls out from a ship on a landing operation during military drills at the Black Sea coast, Crimea, Friday, September 9, 2016. Russia has deployed cruise missiles, multiple rocket launchers, tanks and its latest anti-aircraft system at massive military drills in Crimea. The drills which began across southern Russia and Crimea earlier this week and involve over 120,000 troops are some of the largest exercises Russia has held for years. (Photo by Pavel Golovkin/AP Photo)

A fan gestures next to a police officer while celebrating the life of British singer Keith Flint of techno group “The Prodigy” after his funeral in Braintree, Essex, Britain, March 29, 2019. (Photo by Henry Nicholls/Reuters)

People dancing to buskers performances in Sai Yeung Choi Street South in Mongkok district, Hong Kong, China, 28 July 2018. After 18 years of unregulated street performances, the street performers were forced to give up the space to vehicular traffic again. (Photo by Jerome Favre/EPA/EFE)

A picture made available on 17 July 2015 shows the bright line of the Milky Way above the old oaks at the Rogalin landscape Park in Rogalin village, near Poznan, on the night of 16 July 2015. (Photo by Lukasz Ogrodowczyk/EPA)

Bella Hadid attends “The Unknown Girl (La Fille Inconnue)” Premiere during the 69th annual Cannes Film Festival at the Palais des Festivals on May 18, 2016 in Cannes, France. (Photo by Alberto Pizzoli/AFP Photo)

Mount Sinabung is seen during an eruption from Surbakti village in Karo, North Sumatra, Indonesia, April 20, 2015. The local government is preparing the relocation of residents from three of the villages that were destroyed. (Photo by Tibta Pangin/Getty Images/Anadolu Agency)

Aerial view of CRH bullet trains setting out ahead of Spring Festival travel rush on January 31, 2018 in Hefei, Anhui Province of China. About 2.98 billion trips will be made during the 40-day Spring Festival travel rush. China will take multiple measures to ensure a smooth Spring Festival travel rush. (Photo by VCG/VCG via Getty Images)