Jo Swinson, Leader of the Liberal Democrats takes part in some boxing practice as she campaigns at a boxing gym for young people on November 13, 2019 in London, England. The United Kingdom will hold a general election on December 12. (Photo by Leon Neal/Getty Images)

Vehicles pass through the heavy fog and air pollution that cover Skopje valley in the early morning, in Skopje, The Former Yugoslav Republic of Macedonia, 14 December 2017. According to media reports, Skopje is considered one of the most polluted cities in the world. (Photo by Georgi Licovski/EPA/EFE)

An artist gets ready backstage to perform an Indian art form of dance called “Ottamthullal” at the annual eight-day long Vrischikolsavam festival, which features a colourful procession of decorated elephants along with drum and trumpets concerts, at Sree Poornathrayeesa temple in Kochi, India, December 7, 2018. (Photo by Sivaram V/Reuters)

Santa Claus reacts as (L) Tami McEleney and (R) Patrice Conner whisper in his ear at the King of Prussia Mall, United States' largest retail shopping space, in King of Prussia, Pennsylvania, U.S., December 8, 2018. (Photo by Mark Makela/Reuters)

Indian Hindu sadhus (holy men) from the Juna Akhara take part in a religious procession towards Sangam area, during the first “royal entry” for the Kumbh Mela in Allahabad on December 25, 2018. (Photo by Sanjay Kanojia/AFP Photo)

A man dressed as a devil performs during a Krampus parade in Kaprun, Austria on December 5, 2017. Krampus is a mythical creature that, according to legend, accompanies Saint Nicholas during the festive season. Instead of giving gifts to good children, he punishes the bad ones. (Photo by APA-PictureDesk GmbH/Rex Features/Shutterstock)

Girls take part in the traditional seasonal Christmas run along the streets of Vilnius, Lithuania, Sunday, December 17, 2017. The festive run attracts many hundreds of people to the capital dressed as Santa Clause to take part in the sporting event. (Photo by Mindaugas Kulbis/AP Photo)

In this Saturday, December 30, 2017, picture a girl wearing a bear fur costume takes part in an annual bear parade in Comanesti, Romania. It's a tradition that originated in pre-Christian times, when dancers wearing colored costumes or animal furs went from house to house in villages, singing and dancing to ward off evil. (Photo by Vadim Ghirda/AP Photo)