India's Border Security Force (BSF) soldiers ride their camels during a rehearsal for the “Beating the Retreat” ceremony in New Delhi, India, January 27, 2016. The ceremony symbolises retreat after a day on the battlefield, and marks the official end of the Indian Republic Day celebrations. It is held every year on January 29. (Photo by Anindito Mukherjee/Reuters)

A French farmer leads her cow through the livestock area as preparations continue on the eve of the opening of the International Agricultural Show in Paris, France, February 26, 2016. The Paris Farm Show runs from February 27 to March 6, 2016. (Photo by Benoit Tessier/Reuters)

A woman takes part in the procession of the “Virgem da Atalaia” procession during Holy Week at Alcochete, near Lisbon, Portugal March 27, 2016. Women ride on donkeys during the “Virgem da Atalaia” procession, that has been held annually for about 400 years. In the past, only single women rode the donkeys to ask for help from the Virgin to find a husband. (Photo by Rafael Marchante/Reuters)

In this January 27, 2015 photo, penguins walk on the shore of Bahia Almirantazgo in Antarctica. Antarctica “is big and it's changing and it affects the rest of the planet and we can't afford to ignore what's going on down there”, said David Vaughan, science director of the British Antarctic Survey. (Photo by Natacha Pisarenko/AP Photo)

A North Korean war veteran is decorated with medals as he attends a parade to celebrate the anniversary of the Korean War armistice agreement, Sunday, July 27, 2014 in Pyongyang, North Korea. North Koreans gathered at Kim Il Sung Square as part of celebrations for the 61st anniversary of the armistice that ended the Korean War. (Photo by Wong Maye-E/AP Photo)

Revellers celebrate “Ash Monday” by participating in a colourful “flour war”, a traditional festivity marking the end of the carnival season and the start of the 40-day Lent period until the Orthodox Easter,in the port town of Galaxidi, Greece, February 27, 2017. (Photo by Alkis Konstantinidis/Reuters)

Robot pianist Teo Tronico performs at the World Robot Conference (WRC) 2017 at Etrong International Exhibition & Convention Center on August 22, 2017 in Beijing, China. The World Robot Conference 2017 is held from August 23 to 27 in Beijing. (Photo by Liu Guanguan/China News Service/VCG via Getty Images)

Smoke and flames rise over a warehouse storing ammunition for multiple rocket launcher systems at a military base in the town of Kalynivka in Vinnytsia region, Ukraine September 27, 2017. Ukrainian officials say they have evacuated more than 30,000 people after a fire and ammunition explosions, at the military base on Tuesday. (Photo by Gleb Garanich/Reuters)