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)

Six new Canadians take their oath of citizenship while harnessed on the CN Tower's “Edgewalk” 356 metres (1,168 feet) above Toronto, Ontario, Canada in a still image from video October 9, 2018. (Photo by CN Tower/Handout via Reuters)

A belly dancer performs in a talent show in early morning ceremonies for Groundhog Day on February 2, 2018 in Punxsutawney, Pennsylvania. Punxsutawney Phil, the weather-forecasting groundhog, emerged from his burrow in Pennsylvania on Friday, saw his shadow and predicted six more weeks of winter, despite his rival Staten Island Chuck in New York predicting an early spring. (Photo by Brett Carlsen/Getty Images)

A woman poses with a grenade launcher at a weapons exhibition during festivities marking Marines Day in St.Petersburg, Russia, Saturday, November 24, 2018. (Photo by Dmitri Lovetsky/AP Photo)

Participants gather during a traditional hunting contest, involving tamed golden eagles and hawks, in Almaty, Kazakhstan on December 1, 2018. (Photo by Pavel Mikheyev/Reuters)

Christmas party goers seen on December 14, 2018 in Liverpool, United Kingdom. Revellers hit the bars as they partied hard on the second-to-last Friday before Christmas. (Photo by Mercury Press)

Russian Emergency Situations employees help a girl to bath in the icy water on Epiphany at the Church of the Holy Trinity in Ostankino near TV Tower in Moscow, Russia, Friday, January 18, 2019. Across Russia, the devout and the daring are observing the Orthodox Christian feast day of Epiphany by immersing themselves in frigid water through holes cut through the ice of lakes and rivers. Epiphany celebrates the revelation of Jesus Christ as the incarnation of God through his baptism in the River Jordan. (Photo by Alexander Zemlianichenko/AP Photo)

Traditional dancers from southern state Tamil Nadu prepare themselves as they wait to perform during a press preview of displays being featured for the upcoming Republic Day parade in New Delhi on January 22, 2019. The Republic Day is an annual showcase of India's military hardware and cultural diversity. India celebrates its 70th Republic Day on January 26. (Photo by Sajjad Hussain/AFP Photo)