In this photo taken late Thursday, May 7, 2015, a prison guard, left, and seated inmates cast shadows on a wall while waiting for the beginning of a rock concert by Romanian band Pro Musica, inside the Popa Sapca jail in Timisoara, western Romania. (Photo by Adi Piclisan/AP Photo)

Frogs playing dominos at the Frog Museum, a collection of 108 stuffed frogs in scenes portraying everyday life in the 19th-century and made by Francois Perrier, in Estavayer-le-Lac, Switzerland on November 7, 2018. (Photo by Denis Balibouse/Reuters)

An artist gets ready backstage to perform an Indian art form of dance called “Ottamthullal” at the annual eight-day long Vrischikolsavam festival, which features a colourful procession of decorated elephants along with drum and trumpets concerts, at Sree Poornathrayeesa temple in Kochi, India, December 7, 2018. (Photo by Sivaram V/Reuters)

Malena, 7, looks at Belgian clown Lili Bellule at the pediatric department of the Hopital Erasme at the Universite Libre de Bruxelles (ULB), in Brussels January 27, 2015. The hospital offers performances by musicians and clowns as a form of therapy to help children cope with dealing with the stress and fear caused by hospitalization. (Photo by Yves Herman/Reuters)

A woman works to create handmade Nepali Lokta paper in Kathmandu January 7, 2015. Lokta papers are made from the fibrous inner bark of Lokta bushes that are found over 5,000 metres above sea level. (Photo by Navesh Chitrakar/Reuters)

The New World porcupine, family Erethizontidae, 1280 Gram born at 11 April 2015 Inventory in Zoo. Counting trade Fairs Weighing the Zoo is at 7 May 2015 too the 108 Birthday Zoo Hagenbeck Hamburg, Germany. (Photo by Imago/ZUMA Wire)

A woman looks for fruits to buy inside a bus called Sacolao in Santa Teresa neighborhood in Rio de Janeiro, Brazil, July 7, 2015. The bus, which began operating as a municipal initiative but has been taken over by a private enterprise, arrives every week in some neighborhoods to facilitate families with their grocery shopping and sells food at an affordable price, according to sellers. (Photo by Pilar Olivares/Reuters)

Workers work inside a new Antonov airplane at the Antonov aircraft plant in Kiev, Ukraine, September 7, 2015. State-run aircraft maker Antonov built more than 22,000 units of more than one hundred types and modifications of passenger, transport and special-purpose aircraft, including the world's biggest cargo plane Antonov-225 (Mriya), according to the company's official website. (Photo by Gleb Garanich/Reuters)