Demonstrators protest during a rally against Venezuelan President Nicolas Maduro, in Caracas on April 19, 2017. Venezuela braced for rival demonstrations Wednesday for and against President Nicolas Maduro, whose push to tighten his grip on power has triggered waves of deadly unrest that have escalated the country' s political and economic crisis. (Photo by Juan Barreto/AFP Photo)

Aiden Haas, left, and Lilli Alcala pose after being crowned Mud King and Mud Queen at the 29th annual Mud Day, Tuesday, July 12, 2016 in Westland, Mich. The event, open to children 12 and younger, was at the Hines Park-Nankin Mills Area west of Detroit. Children 12 and younger were able to slosh around in the pit while participating in mud limbo, wheelbarrow races and other free activities. (Photo by Carlos Osorio/AP Photo)

Law enforcement officers clash with protesters, Wednesday, July 20, 2016, in Cleveland, during the third day of the Republican convention. (Photo by John Minchillo/AP Photo)

American Paralympic snowboarder Amy Purdy dances with a robot during the opening ceremony of the Rio 2016 Paralympic Games at the Maracana stadium in Rio de Janeiro on September 7, 2016. (Photo by Yasuyoshi Chiba/AFP Photo)

Two keepers at the Australian Reptile Park in New South Wales struggle with Leonardo, an alligator snapping turtle weighing 45 kilos at the park in Gosford, NSW 2 July 2015. The 50cm long Leonardo – who was smuggled illegally into Australia and found in a Sydney sewer in November 2000 – was removed from his tank for an annual health check. And as a gesture to onlooking press photographers demonstrated his strength by snapping a piece of bamboo in half. (Photo by EPA/HO)

Cuban girls dressed as nurses and a lizard wait for their turn to dance during a visit by the Gay Men's Chorus of Washington in Havana July 13, 2015. The choir made its first appearance on July 12, 2015 in Cuba as part of a tour that will include a dozen concerts in the context of the restoration of relations between the island and the United States. (Photo by Enrique de la Osa/Reuters)

England supporters in the Flat Iron Square pub in London react to events in Kaliningrad, where England and Belgium play to decide the winner of Group G in the Russia 2018 World Cup on June 28, 2018. (Photo by Daniel Leal-Olivas/AFP Photo)

A boy sits on the back of a crocodile on May 19, 2018 at a pond in Bazoule in Burkina Faso, a village which happily shares its local pond with “sacred” crocodiles. Crocodiles may be one of the deadliest hunters in the animal kingdom, but in a small village in Burkina Faso it is not unusual to see someone sitting atop one of the fearsome reptiles. According to local legend, the startling relationship with the predators dates back to at least the 15 th century. The village was in the grip of an agonising drought until the crocodiles led women to a hidden pond where the population could slake their thirst. (Photo by Olympia de Maismont/AFP Photo)