Revellers dressed as zombies take part in an enactment of the running of the bulls a day before the start of the San Fermin festival in Pamplona, northern Spain, July 5, 2016. (Photo by Eloy Alonso/Reuters)

Revellers take part in the annual “Naval Battle” of Vallecas during the Virgen del Carmen Festival in Madrid, Spain July 17, 2016. (Photo by Javier Barbancho/Reuters)

2016 Rio Olympics, Opening ceremony, Maracana, Rio de Janeiro, Brazil on August 5, 2016. Athletes of Colombia take part in the opening ceremony. (Photo by Kai Pfaffenbach/Reuters)

Military enthusiasts take part in a re-enactment of the World War II battle of Stalingrad at the “Stalin Line” memorial, near the village of Goroshki, Belarus, February 27, 2016. (Photo by Vasily Fedosenko/Reuters)

Female Kurdish Peshmerga take part their graduation ceremony at a police academy in Zakho district of the Dohuk Governorate of the Iraqi Kurdistan province, Iraq March 30, 2016. (Photo by Ari Jalal/Reuters)

Rebel fighters from the Ahrar al-Sham Islamic Movement fire a heavy machine gun during what they said was an offensive to take the northwestern city of Idlib March 24, 2015. (Photo by Khalil Ashawi/Reuters)

Participants wearing East Asian traditional costumes take photos during the 88th annual Hollywood Christmas Parade in Hollywood, Californi​a, USA, 01 December 2019. (Photo by Christian Monterrosa/EPA/EFE)

Swimmers take part in the annual Christmas Day swim in Porthcawl, Wales, England on December 25, 2019. (Photo by Ben Birchall/PA Images via Getty Images)