Sudanese protesters rally outside the army complex in Sudan's capital Khartoum on April 18, 2019. Huge crowds of protesters thronged the Sudanese capital Khartoum today, a week after the army's ouster of president Omar al-Bashir, determined to complete their revolution seeking civilian rule. (Photo by Ozan Kose/AFP Photo)

Players in action during the Swamp Soccer Championships 2019 in Hyrynsalmi, Finland, 19 July 2019. The World Championship in swamp football is played annually on Vuorisuo bog in Hyrynsalmi. (Photo by Tomi Hanninen/EPA/EFE)

A Spanish national police officer uses his club to hit a protester during a demonstration called the Catalan pro-independence left youth group “Arran” on October 19, 2019 in Barcelona, a day after nearly 200 people were hurt in another night of violent clashes in Catalonia. The deterioration came on the fifth consecutive day of protests in the Catalan capital and elsewhere over a Spanish court's jailing of nine separatist leaders on sedition charges over a failed independence bid two years ago. (Photo by Josep Lago/AFP Photo)

Cambridge students the morning after the Trinity and Jesus college May Balls in Cambridge, United Kingdom on June 19, 2018. Students at Cambridge University celebrate the end of the academic year with the May Balls. (Photo by South West News Service)

Principle Ballet Dancer, Ekaterina Bulgutova, of the Russian State Ballet, with the Nutcracker part of Christmas Ballet Season in Cardiff which starts at St Davids Hall on December 20, 2016 in Cardiff, England. (Photo by Kiran Ridley/Barcroft Images)

Chilean police officers march with the puppies of future police dogs during the annual military parade at the Bernardo O'Higgins park in Santiago, Chile, September 19, 2018. (Photo by Rodrigo Garrido/Reuters)

Mini-pigs perform during the presentation in Balashikha, Russia on December 19, 2018. (Photo by Maxim Shemetov/Reuters)

A woman dressed up as a zombie participates in a zombie walk in Stockholm, Sweden on August 19, 2017. (Photo by Jonathan Nackstrand/AFP Photo)