An election poster calling for the legalisation of marijuana and featuring internet meme “Grumpy Cat” hangs outside the Pirate Party's campaign headquarters in Berlin on August 16, 2013. The Pirates, who to everyone's surprise were elected into Berlin's regional parliament in September 2011, are trying to capitalise on their recent electoral gains in upcoming parliamentary elections, running on a platform of transparency in government. Germany goes to the polls on September 22, 2013. Placard reads: “Hurry up, my dope is everything”. (Photo by John Macdougall/AFP Photo)

Couples take part in the “Love and Challenge Marathon” in Hanoi, Vietnam, 16 August 2015. Fifty couples, who are going to get married, participated in the event which is held the fifth time. This year, the winners of the marathon received a honeymoon trip to Malaysia. (Photo by Luong Thai Linh/EPA)

Syrians gather during an evacuation operation of rebel fighters and their families from rebel-held neighbourhoods on December 15, 2016 in the embattled city of Aleppo. A convoy of ambulances and buses left rebel territory in Aleppo in the first evacuations under a deal for opposition fighters to leave the city after years of fighting. The rebel withdrawal will pave the way for President Bashar al-Assad's forces to reclaim complete control of Syria's second city, handing the regime its biggest victory in more than five years of civil war. (Photo by Karam Al-Masri/AFP Photo)

A baby pangolin sits with its mother inside a cage prior to their release into the wild in Sibolangit, North Sumatra, Indonesia, Monday, April 27, 2015. The anteaters are part of dozens of live pangolins and around five tons (11,000 lbs) of pangolin meat ready to be shipped abroad confiscated in a police a raid last week. (Photo by Binsar Bakkara/AP Photo)

Joshua Patino stands on a ladder to put finishing touches on a giant dinosaur exhibit at PAX East in the Boston Convention and Expo Center, Thursday, April 21, 2016, in Boston. PAX East, an annual celebration of gaming culture, is expected to draw tens of thousands of visitors Friday through Sunday. It's a place where serious gamers can preview unreleased video games and devices, compete in tournaments, hear live music and meet others for whom gaming is a way of life. (Photo by Elise Amendola/AP Photo)

A woman walks past graffiti in Beirut, Lebanon, Wednesday, May 4, 2016. Graffiti artists have been trying to re-engage disillusioned youth in a debate about the country's latest wave of political turmoil. (Photo by Hassan Ammar/AP Photo)

This undated handout photo received from the Antarctic Ocean Alliance on October 28, 2016 shows a adelie penguin jumping onto the ice in the Ross Sea in Antarctica. The world's largest marine reserve aimed at protecting the pristine wilderness of Antarctica will be created after a “momentous” agreement was finally reached on October 28, 2016 with Russia dropping its long-held opposition. (Photo by John Weller/AFP Photo/Antarctic Ocean Alliance)

A Tibetan Buddhist nun spins a prayer wheel in sub zero temperatures at a Buddhist laymen lodge where thousands of people gather for daily chanting session during the Utmost Bliss Dharma Assembly, the last of the four Dharma assemblies at Larung Wuming Buddhist Institute in remote Sertar county, Garze Tibetan Autonomous Prefecture, Sichuan province, China November 1, 2015. (Photo by Damir Sagolj/Reuters)