Syrian Internal Security Forces dance in celebration during their graduation ceremony, at Ain Issa desert base, in Raqqa province, northeast Syria, Thursday, July 20, 2017. Some 250 residents of Syria's Raqqa province are the latest batch to graduate from a brief U.S-training course that is preparing an internal security force to hold and secure areas as they are captured from Islamic State militants. (Photo by Hussein Malla/AP Photo)

Convicted murderer Hector Alvarado Mazariegos, right, drops to the ground as he is hit by bullets of a Guatemala firing squad in the public cemetery at Mazatenango, June 28, 1975. His companion, Rocael Ortiz, met the same fate a few seconds later. Both were convicted of murder. (Photo by AP Photo/Anzueto)

Sloth “Paula” hangs from a branch in her enclosure at the zoo in Halle an der Saale, eastern Germany, on June 14, 2019. The two-toed sloth celebrated her 50th birthday and is, according to the zoo, the oldest sloth of the world. (Photo by Hendrik Schmidt/dpa/AFP Photo)

A man wearing a costume dives into a partly frozen lake in Shenyang, in China's northeastern Liaoning province on February 19, 2019. (Photo by AFP Photo/China Stringer Network)

A motorcycle-taxi driver takes a nap while leaning on his bike along a street in Bangkok, Thailand on February 17, 2019. (Photo by Jewel Samad/AFP Photo)

Boys contort their faces as they participate in a game where they need to slide a coin from their forehead to their mouth to win, during the annual Feast Day of St. Rita of Cascia in Manila, Philippines on May 19, 2019. (Photo by Noel Celis/AFP Photo)

Former Playboy Bunny Angie Best prepares backstage ahead of her return as the iconic Bunny Mother exclusively at the Telling Tales event at Playboy Club London on September 21, 2017 in London, England. (Photo by Tim P. Whitby/Tim P. Whitby/Getty Images for Playboy)

In this Wednesday, November 15, 2017 photo, a woman poses for a selfie with the carcass of a humpback whale on Ipanema beach, in Rio de Janeiro, Brazil. Biologist Rafael Carvalho said the whale appears to have been dead for a few days. Authorities were urging beachgoers who had flocked to Ipanema on a national holiday to stay away from the animal. (Photo by Silvia Izquierdo/AP Photo)