A woman aims a World War II machine gun at a military show during celebration of the Defenders of the Fatherland Day in St.Petersburg, Russia, Tuesday, February 23, 2016. The day, celebrated in Russia on February 23, honors the nation's military and is a nationwide holiday. (Photo by Dmitri Lovetsky/AP Photo)

Participants, one of them loosing balance, jump in a sack race at a shopping center in Paris to win a 500 euros voucher (537 USD), on the first day of the winter sales in Paris, France, Wednesday, January 6 , 2016. The five-week 2016 winter sales start everywhere across France on Wednesday Jan. 6 and end on Feb. 16. (Photo by Francois Mori/AP Photo)

View of an egg fried on the pavement in Pozo Hondo, Santiago del Estero, Argentina on January 23, 2016, while the real feel was 57 degrees Celsius. Pozo Hondo's Mayor Claudio Nicolau fried an egg on the pavement of the main square of the city Saturday. (Photo by AFP Photo/Stringer)

A worker pauses for a sandwich, resting on a girder during the construction of a skycraper. (Photo by Hulton Archive/Getty Images). Circa 1930

Two guards perform an execution in China, one holding the gun, the other holding a mask over the victim's face. (Photo by General Photographic Agency/Getty Images). Circa 1925

Dubai is now home to what has been billed as the world’s largest indoor dog park, complete with customised luxury suites, 24/7 webcams, flat screen TVs and orthopedic mattresses. Launched during Easter at Dubai Investment Park, My Second Home already has many takers with 40 of its 200 residential luxury rooms booked for summer. Here: a dog sits on its bed at My Second Home, a newly opened luxury pet resort and spa, in Dubai, April 24, 2015. (Photo by Ahmed Jadallah/Reuters)

Vehicles move past a man resting on a taxi, as he waits for passengers, along a road in Karachi, Pakistan, May 5, 2015. (Photo by Akhtar Soomro/Reuters)

People cool off in a fountain outside the Southbank Centre on June 30, 2015 in London, England. The UK is currently experiencing a heatwave, with temperatures of 35 degree celsius forecast tomorrow in some parts of the country. The extreme heat has already seen train cancellations and a health warning has been issued. (Photo by Rob Stothard/Getty Images)