A woman smokes marijuana during the annual 4/20 marijuana rally on Parliament Hill in Ottawa, Ontario, Canada, April 20, 2017. (Photo by Chris Wattie/Reuters)

Juanita Robinson (L) from Ohio and Trenaya Blackburn pose as Quan White from Michigan takes their picture as they vacation on South Beach on May 16, 2016 in Miami Beach, Florida. The Florida government announced it broke a tourism record in the first quarter of this year, attracting 29.8 million tourists, an increase of 4.8 percent over the same time frame in 2015. (Photo by Joe Raedle/AFP Photo)

Revellers in fancy dress enjoy the atmosphere during the British Fancy Dress Day on November 12, 2015 in Benidorm, Spain. The British Fancy Dress Day is one of the biggest fancy dress parties in Europe and is held the day after the Benidorm fiestas in November. The tradition started over 20 years ago when Manolo from Sinatras Club offered a free drink to anyone who dress up. Nowadays around 30,000 people, mostly British Expats living in Spain and tourists visiting the Costa Blanca resorts, attends, attend the event. (Photo by David Ramos/Getty Images)

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)

Armed Syrian Turkmen villagers are seen near the northern Syrian village of Yamadi, near the Turkish-Syrian border, Syria, November 24, 2015. Turkey shot down a Russian warplane near the Syrian border on Tuesday saying it had repeatedly violated its air space, one of the most serious publicly acknowledged clashes between a NATO member country and Russia for half a century. (Photo by Reuters/Stringer)

Indian School children's in a traditational attire of a characters of Indian epic Ramayan, on the eve of children's day celebration at cubbon park, in Bangalore, India, 13 November 2016. Children's day (also known as Bal Divas), in India is celebrated every year on 14th of November to increase the awareness of people towards the rights, care, and education of children. Many schools hold activities and allow students to have fun and attend their classes in coloured dresses. (Photo by Jagadeesh N.V./EPA)

A performer wearing costumes walk on stilts before a show during a lantern fair at the beginning of Chinese Lunar New Year, in Xi'an, Shaanxi province, February 11, 2016. (Photo by Reuters/Stringer)

Mario Huettenhofer, chief of the German company 3D Fab, presents his own face as 3d print during the international fairs FabCon 3.D and Rapid.Tech in Erfurt, Germany, Thursday, May 15, 2014. 130 exhibitors from all over the world present the entire world of 3D printing. The trade fairs are accompanied by specialist programs featuring 80 scientists, practitioners and trend analysts from ten countries, who will explain the latest findings, trends and applications for additive processes in industry and for 3D printing in the private sector to newcomers, experts and consumers alike. (Photo by Jens Meyer/AP Photo)