A Ukrainian serviceman fires a 2S7 Pion self-propelled gun during military exercises near the village of Divychky in Kiev region, Ukraine, October 21, 2016. (Photo by Valentyn Ogirenko/Reuters)

Indonesian tourists take a selfie as Mount Bromo spews volcanic material and ash into the air during an eruption in Probolinggo, East Java, Indonesia, 31 December 2015. Indonesia's Mount Bromo is on the second highest alert level as its activity has increased in the last two months. (Photo by Fully Handoko/EPA)

A couple joke as they walk on the beach on August 22, 2018 in Wonsan, North Korea. (Photo by Carl Court/Getty Images)

A peformance artist attends an election rally for Cameroon presidential candidate for the opposition Univers party, Cabral Libii in Yaounde, Cameroon 06 October 2018. Africa's oldest president Paul Biya who has been in power since 1982 is up against eight candidates when voters go to the polls 07 October 2018. 6.9 million registered voters will head to the polls but marginalised anglophone separatists in the North West and South West of the country threaten to disrupt the elections. (Photo by Nic Bothma/EPA/EFE)

Artists from the Beijing Dance Academy perform to celebrate the Chinese Lunar New Year in Budapest, capital of Hungary, February 6, 2019. (Photo by Attila Volgyi/Xinhua News Agency/Barcroft Media)

People stand by a damaged car at a train station at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, May 10, 2016. (Photo by Marko Djurica/Reuters)

Filipino firemen extinguish a burning vehicle during an earthquake preparedness drill in Makati city, south of Manila, Philippines, 22 June 2016. Thousands of people participated in the Metro Manila earthquake drill to prepare residents of nearly 12 million for a feared magnitude-7.2 quake that could kill thousands and displace millions, Emerson Carlos head of the Metropolitan Manila Development Authority (MMDA) said. Philippines sits on the Pacific Ring of Fire, an area prone to seismic shifts that spark earthquakes and volcanic activity. (Photo by Francis R. Malasig/EPA)

A Hindu holy man or Sadhu walks back to his ashram after taking a dip at Sangam, confluence of Ganges river, Yamuna river and mythical Saraswati river in Allahabad, India, Thursday, August 4, 2016. (Photo by Rajesh Kumar Singh/AP Photo)