A passenger without pants waits for the subway train during “The No Pants Subway Ride” in Mexico City January 11, 2015. The event, the fifth organized in Mexico, is an annual flash mob and occurs in different cities around the world, according to its organisers. (Photo by Edgard Garrido/Reuters)

A visitor takes in a view of the downtown district from Twin Peaks on Friday, January 9, 2015, in San Francisco. (Photo by Marcio Jose Sanchez/AP Photo)

A swimmer competes during the UK Cold Water Swimming Championships at Tooting Bec Lido in south London January 24, 2015. (Photo by Luke MacGregor/Reuters)

Men eat oranges from a push cart along a road as a vehicle travels past them in Karachi January 22, 2015. (Photo by Akhtar Soomro/Reuters)

A man plays in front of a wave crashing into Beirut's Corniche, a seaside promenade, as high winds sweep through Lebanon ahead of an impending storm January 6, 2015. (Photo by Jamal Saidi/Reuters)

A pro-independence protester sits in front of Catalonia's regional parliament as lawmakers vote inside, in Barcelona, January 16, 2014. (Photo by Albert Gea/Reuters)

Pupils participate in a calligraphy contest to celebrate the New Year in Tokyo January 5, 2016. Over 3,000 calligraphers who qualified in competitions throughout Japan wrote resolutions or wishes onto paper sheets during the annual contest that marks the start of the new year, according to organizers. (Photo by Thomas Peter/Reuters)

Jason Derulo (C) performs “Get Ugly” at the People's Choice Awards 2016 in Los Angeles, California January 6, 2016. (Photo by Mario Anzuoni/Reuters)