Revellers cool themselves in the Danube River during the Sziget music festival on an island in Budapest, Hungary August 12, 2015. The event is one of the biggest cultural events of Europe, offering art exhibitions, theatrical and circus performances and music concerts. Almost 200 performers from 47 countries will entertain the hundreds of thousands of visitors from 11 to 18 August. (Photo by Laszlo Balogh/Reuters)

A girl plays with colourful papers at the 23rd Sziget (Island) Festival on Shipyard Island in Budapest, Hungary, 13 August 2015. The festival is one of the biggest cultural events of Europe, offering art exhibitions, theatrical and circus performances and music concerts. Almost 200 performers from 47 countries will entertain the hundreds of thousands of visitors from 11 to 18 August. (Photo by Balazs Mohai/EPA)

In this February 4, 2016 picture a masked participant of the traditional carnival parade poses in the streets of the village of Kippel in the Loetschental valley, southwestern part of Switzerland. During this sinister carnival, participants wearing wooden masks and animal furs, crowd the streets of the villages to scare the people. (Photo by Dominic Steinmann/Keystone via AP Photo)

Bjorn, aged 5, smiles as he poses with a Owl butterfly during an event to launch the Sensational Butterflies exhibition at the Natural History Museum in London, Britain March 23, 2016. The exhibition opens to the public on March 24 and runs until September 11. (Photo by Dylan Martinez/Reuters)

Kanphitcha Sungsuk, 21, (C), lines up with young men to speak to officers during an army draft held at a school in Klong Toey, the dockside slum area in Bangkok, Thailand, April 6, 2017. Thailand is widely seen as a paradise for gay and transgender people, but many complain of being treated as second-class citizens and the obligation to respond to the draft can be a nightmare when they turn 21. (Photo by Athit Perawongmetha/Reuters)

The players of Denmark huddle prior to the FIFA Women's World Cup qualifier match between Denmark and Sweden at Viborg Stadion on September 4, 2018 in Viborg, Denmark. (Photo by Lars Ronbog/FrontZoneSport via Getty Images)

Workers pull apart a house in Khandyga, Russia, on February 2, 2018. The shifting ground caused by the uneven thawing of permafrost each summer causes buildings like this Soviet-era apartment house to sag and collapse. (Photo by Amos Chapple/Radio Free Europe/Radio Liberty)

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)