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, Britain October 17, 2016. The weekend, which begins on Sunday, involves rituals for new students, culminating in a foam fight on Monday morning. (Photo by Russell Cheyne/Reuters)

A layer of morning mist still covers the fields as the sun rises into the morning sky over Hohenfelden, Thuringia state, Germany, early 07 September 2016. Meteorologists predict the weather to become warm and sunny in the region with temperatures reaching around 256 degrees Celsius. (Photo by Martin Schutt/EPA)

Performers dressed as Ded Moroz, the equivalent of Santa Claus, and his granddaughter Snegurochka (Snow Maiden) take on shoe covers as they visit the Republican Scientific and Practical Centre of Pediatric Surgery in Minsk, Belarus, December 28, 2016. (Photo by Vasily Fedosenko/Reuters)

Students attend a stewardess skill training for the upcoming 2017 entrance examination for art majors in colleges in Luoyang, central China's Henan Province, January 4, 2017. Along with how to stand, how to sit is also covered in these classes. (Photo by Li Bo/Xinhua/Barcroft Images)

Snow covered mountains are seen from the waters of Unstad along the northern Atlantic Ocean on March 12, 2017, where the water temperatures is at five degrees centigrade and the air temperature is at minus two degrees centigrade. Unstad, the world' s most northern surf school, is perfect for those wanting to experience Arctic Surfing. (Photo by Olivier Morin/AFP Photo)

A woman covers her face as a fire burns in the middle of town during an anti-G20 protest on July 7, 2017 in Hamburg, Germany. Authorities are braced for large-scale and disruptive protests as Leaders of the G20 group of nations arrive in Hamburg for the July 7-8 G20 summit. (Photo by Leon Neal/Getty Images)

A reveller covered in paint takes part during the annual Cascamorras festival in Guadix, southern Spain September 9, 2015. The festival was inspired by a dispute between the town of Baza and Guadix over the possession of an icon of the Virgin of Piedad. The Cascamorras refers to representatives from Guadix, who were sent to Baza to recover the statue. As the Cascamorras had to stay perfectly clean to gain possession of the statue, Baza residents attempt to make them as “dirty” as possible. (Photo by Marcelo del Pozo/Reuters)

A male red deer with antlers covered in bracken, walks through undergrowth in Richmond Park in south west London, October 3, 2014. Over 600 red and fallow deer roam in the largest of London's Royal Parks, and have their numbers managed in an annual cull each November and February. (Photo by Toby Melville/Reuters)