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 model wears a floral head dress as she promotes a chain of garden centres at the Royal Horticultural Soceity's Chelsea Flower Show in London, Britain, May 18, 2015. (Photo by Toby Melville/Reuters)

Shane Baker of Minnesota poses for a photo with adult film actress Rachel Starr at the Pornhub booth at the 2017 AVN Adult Entertainment Expo at the Hard Rock Hotel & Casino on January 18, 2017 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images)

A competitor poses on the catwalk during the Miss Bumbum Brazil 2016 pageant in Sao Paulo, Brazil on November 9, 2016. Fifteen candidates compete in the annual pageant to select Brazil' s sexiest female rear end. (Photo by Miguel Schincariol/AFP Photo)

The chariot of God Bhairab is pulled through the city centre of Bhaktapur near Kathmandu during the Bisket festival April 10, 2015. The festival, which runs for more than a week and coincides with the Nepalese New Year, involves devotees offering prayers and the pulling of two chariots, one carrying the idol of God Bhairab and the other with the idol of Goddess Bhadrakali, around the ancient city of Bhaktapur. Devotees participate in the festival with the belief that they will be blessed with good health, fortune and harvest for the coming year. (Photo by Navesh Chitrakar/Reuters)

A handout picture provided by Global newsroom of Czech Martin Sonka (C) leading Nigel Lamb (top) of Great Britain and Yoshihide Muroya of Japan (down) along the Mount Fuji prior the third stage of the Red Bull Air Race World Championship in Chiba, Japan on June 1, 2016. (Photo by Predrag Vockovic/EPA/Global Newsroom)

A Humboldt penguin stands on weighing scales whilst being photographed by members of the press during a photocall at the annual weigh-in at London Zoo in London, Britain, 24 August 2016. Every animal that is in the zoo is weighed and measured and the statistics recorded so the data can be shared with zoos across the world. (Photo by Hannah McKay/EPA)

A man is silhouetted as he stands on a walkway in the sky lobby at the Chancellery, the seat of German Chancellor Angela Merkel (not pictured) in Berlin, May 7, 2014. (Photo by Thomas Peter/Reuters)