Two boys look out from the Mangueira slum towards the Maracana Stadium that is hosting the Rio's 2016 Summer Olympics opening ceremonies, in Rio de Janeiro, Brazil, Friday, August 5, 2016. (Photo by Leo Correa/AP Photo)

A woman waits at a polio immunisation health centre, in Maiduguri, Borno State, Nigeria, August 29, 2016. Nigeria's military has liberated large swathes of land from Boko Haram but a ride with an army convoy, all guns firing for fear of ambush, shows how far the northeast is from normality after a brutal Islamist insurgency that has displaced millions. (Photo by Afolabi Sotunde/Reuters)

Two white storks stand close to each other on their nest on a tree in Zerbolo, Italy, Thursday, October 26, 2017. (Photo by Antonio Calanni/AP Photo)

Actress Lindsay Lohan and DJ Samantha Ronson attend the Charlotte Ronson Spring 2009 fashion show during Mercedes-Benz Fashion Week at The Promenade in Bryant Park on September 6, 2008 in New York City. (Photo by Stephen Lovekin/Getty Images for IMG)

Thailand’s Surasak Waenwiset tries a shot as Hungary’s Marcell Fenyvesi stands nearby, during their Beach Handball Men’s Tournament match in Tecnopolis Park, during the Youth Olympic Summer Games in Buenos Aires, Argentina on October 9, 2018. (Photo by Florian Eisele/AP Photo)

Students from St Andrews University are covered in foam as they take part in the traditional Raisin Weekend in the Lower College Lawn, at St Andrews in Scotland on October 22, 2018. The “raisin weekend” stems from a gift of raisins (now flour and foam) traditionally given by a first year student to their academic “parents” in gratitude for their guidance. (Photo by Russell Cheyne/Reuters)

Cooler temperatures begin this week as a polar vortex brings much colder conditions with the chance of snow for Snowdonia, Ogwen Valley, North Wales on 22nd October 2018. The Ogwen Valley and Tryfan Mountain looking splendid in the Autumn sunrise. (Photo by DGDImages/Alamy Live News)

A man passes at the displayed art installation “Middle way” by Romanian artist Bogdan Rata in Kiev, Ukraine, Tuesday, November 20, 2018. The monument set on the central Kiev street of Khreshchatyk, at the place of Vladimir Lenin monument which was destroyed in 2013 during the Maidan events. (Photo by Efrem Lukatsky/AP Photo)