A zookeeper feeds a hippopotamus with a watermelon in its enclosure in Belgrade's zoo, Serbia, July 20, 2015. Temperatures in Serbia have risen up to 40 degrees Celsius (104 degrees Fahrenheit), according to official meteorological data. (Photo by Marko Djurica/Reuters)

Peter Dinklage, left, and Lena Headey attend the 67th Primetime Emmy Awards on Sunday, September 20, 2015, at the Microsoft Theater in Los Angeles. (Photo by Alex Berliner/Invision for the Television Academy/AP Images)

A supporter of China's President Xi Jinping waits on the Mall for him to pass during his ceremonial welcome, in London, Britain, October 20, 2015. Xi is on a State visit to Britain. (Photo by Peter Nicholls/Reuters)

Fashion fans pose outside the main catwalk venue during London Fashion Week Spring/Summer 2017 in London, Britain September 20, 2016. (Photo by Neil Hall/Reuters)

Singer Ariana Grande (C) performs “Side by Side” during the 2016 American Music Awards in Los Angeles, California, U.S., November 20, 2016. (Photo by Mario Anzuoni/Reuters)

Friends and relatives mourn by the coffin during the wake for Florjohn Cruz, who was killed in a police drugs buy-bust operation, in Manila, Philippines late October 20, 2016. (Photo by Damir Sagolj/Reuters)

Festivalgoers are seen during the 2019 Coachella Valley Music And Arts Festival on April 20, 2019 in Indio, California. (Photo by Emma McIntyre/Getty Images for Coachella)

Supporters of Venezuela's President Nicolas Maduro take part in a rally in support of the government in Caracas, Venezuela on May 20, 2019. (Photo by Ivan Alvarado/Reuters)