A commuter gestures to Boris Johnson as he rides across Vauxhall Bridge in London, England on November 19, 2015. The London mayor was opening a cycle superhighway. (Photo by John Stillwell/PA Wire)

A Saudi soldier fires a mortar towards Houthi movement position, at the Saudi border with Yemen April 21, 2015. (Photo by Reuters/Stringer)

Principle Ballet Dancer, Ekaterina Bulgutova, of the Russian State Ballet, with the Nutcracker part of Christmas Ballet Season in Cardiff which starts at St Davids Hall on December 20, 2016 in Cardiff, England. (Photo by Kiran Ridley/Barcroft Images)

In this Thursday, August 11, 2016, photo, the injured are helped after a bomb blast in the southern resort city of Hua Hin, 240 kilometers (150 miles) south of Bangkok, Thailand. Police are investigating a series of bomb blasts in Hua Hin and other cities in Thailand. (Photo by Daily News via AP Photo)

Members of security forces secure Tahrir Square in Cairo, Egypt, November 11, 2016. Egypt imposed a big security clampdown in its cities on Friday as mass demonstrations called to protest against austerity measures failed to take place. Riot police and armored vehicles filled the otherwise empty streets of central Cairo, but most people stayed at home. (Photo by Mohamed Abd El Ghany/Reuters)

A dead whale is seen on the shore of the Ipanema beach in Rio de Janeiro, Brazil November 15, 2017. A biologist, Rafael Carvalho, said on Wednesday the whale appeared to have been dead for a few days. Authorities were urging beachgoers who had flocked to Ipanema on a national holiday to stay away from the animal. However, many were spotted near the carcass with some people playing in the water nearby. The whale is approximately 39 feet (12 metres) long and weighs about 25 tonnes. (Photo by Pilar Olivares/Reuters)

Yokozuna-ranked sumo wrestler Hakuho of Mongolia (top) throws Goeido of Japan during their bout on the final day of the 15-day Kyushu Grand Sumo Tournament in Fukuoka on November 26, 2017. Mongolian grand champion Hakuho won the latest sumo tournament on November 25 as Japan's national sport continued to draw media attention after another top wrestler faced a police probe into an alleged assault. He won the 15-day tournament at 13-1 by Saturday with one day remaining as his closest contenders were all defeated at 11-3 before his bout on the day. (Photo by AFP Photo/JIJI Press)

Tourists ride a cable car in the form a of a Chiva, a bus used to serve rural routes, in Pitalito, Colombia, Tuesday, April 5, 2017. The ride called “La Chiva Voladora” costs about $0.70 and you zip along about 800 meters from one side of a hill to another. (Photo by Fernando Vergara/AP Photo)