College students shout slogans during a pep rally organised to boost their morale ahead of their job hunting in Tokyo, Japan March 1, 2017. (Photo by Kim Kyung-Hoon/Reuters)

Edibles are displayed at Shango Cannabis shop on first day of legal recreational marijuana sales beginning at midnight in Portland, Oregon October 1, 2015. The sale of marijuana for recreational use began in Oregon on October 1, 2015 as it joined Washington state and Colorado in allowing the sale of a drug that remains illegal under U.S. federal law. (Photo by Steve Dipaola/Reuters)

Gorillas sit next to a ruler during a photocall for the annual weigh-in at London Zoo in London, Britain August 24, 2017. During the weigh-in, animals across the zoo have their vital statistics recorded including their height and weight and the information is then shared with zoos across the world to help zookeepers compare important information on thousands of endangered species. (Photo by Neil Hall/Reuters)

Humboldt Penguins swim in their pool as a keeper looks on through a spherical window during the annual stocktake press preview at London Zoo in Regents Park in London Monday, January 4, 2016. A requirement of ZSL London Zoo's license, the annual audit takes keepers a week to complete and all of the information is shared with zoos around the world via the International Species Information System, where it's used to manage the worldwide breeding programmes for endangered animals. (Photo by Alastair Grant/AP Photo)

An Afghan street vendor carries bread on his head ahead of the upcoming holy fasting month of Ramadan in Kabul, Afghanistan, Sunday, June 5, 2016. Muslims across the world will be observing the holy fasting month of Ramadan, when they refrain from eating, drinking and smoking from dawn to dusk. (Photo by Rahmat Gul/AP Photo)

Miss USA Alyssa Campanella arrives at the 2nd Annual American Giving Awards at the Pasadena Civic Auditorium on December 7, 2012 in Pasadena, California. (Photo by Gregg DeGuire/WireImage)

A worker prepares the “Cutter Head” of the Port Tunnel boring machine for attachment to the tunneling machine on September 1, 2011 in Miami, Florida. The $45 million machine is longer than a football field and about as tall as a four-story building and it will carve the twin tunnels connecting Watson Island and Dodge Island. The the new $1 billion Port of Miami tunnel is expected to be completed in May of 2014. (Photo by Joe Raedle/Getty Images)

A fishmonger prepares fresh festive seafood supplies at the Sydney Seafood Market on December 23, 2011 in Sydney, Australia. The annual 36-hour seafood marathon commenced today with thousands of Sydney shoppers expected to flock to the Sydney Seafood Market to find the freshest possible seafood catch for Christmas Day feasts. (Photo by Brendon Thorne/Getty Images)