LiLou the therapy pig stands in front of a departures board at San Francisco International Airport in San Francisco, California, U.S. October 4, 2019. (Photo by Jane Ross/Reuters)

In this Monday, July 24, 2017 photo, a police officer walks in front of a mural during a protest demanding an end to the current pension fund system, in Santiago, Chile. Protesters say the government pension system robs retirees of fair pension payments, and are demanding a new social security system with higher payments. (Photo by Esteban Felix/AP Photo)

Bluebella Lingerie advertising photo shoot, Oxford Circus, London, Great Britain on September 14, 2017. Bluebella has staged its most daring lingerie campaign yet, sending 19 models to strut their stuff in skimp smalls on one of London's busiest junctions. Bluebella organised the show early in the morning to minimise congestion ahead of London Fashion Week which starts on Friday 15th September. The “models” included a medical PA, a company boss, four students, two actors, a musician and two writers. (Photo by Cavendish Press/LESAUVAGE/Bluebella)

An Afghan boy looks through the scope of a toy gun, as other children ride on swings during the first day of the Muslim holiday of Eid al-Fitr, which marks the end of the holy month of Ramadan, in Kabul, Afghanistan June 25, 2017. (Photo by Omar Sobhani/Reuters)

A man walks his dog as the sun sets in a park in Frankfurt, Germany, Monday, September 18, 2017. Cool damp weather is set to continue in this part of Germany for the next few days with temperatures in the mid teens Celsius. (Photo by Michael Probst/AP Photo)

Chloe Lewis attends “The Ony Way Is Essex” season finale filming in Wintney, Hook, England on October 29, 2017. (Photo by Beretta/Sims/Rex Features/Shutterstock)

An army dog stands up as retiring soldiers salute their guard post before retirement in Suqian, Jiangsu province, China on November 29, 2017. (Photo by Reuters/China Stringer Network)

Armed female members of the militant Palestinian group Islamic Jihad carry Kalashnikov assault rifles as they take part in a rally to protest against US President Donald Trump's decision to recognise Jerusalem as the capital of Israel, in Gaza City on December 11, 2017. (Photo by Mohammed Abed/AFP Photo)