Robot Xian'er is placed in the main building of Longquan Buddhist temple for photographs by the temple's staff, on the outskirts of Beijing, April 20, 2016. (Photo by Kim Kyung-Hoon/Reuters)

Iranian demonstrators burn an Israeli flag during a rally marking al-Quds (Jerusalem) Day in Tehran July 10, 2015. (Photo by Reuters/Stringer/TIMA)

CANNES, FRANCE - NOVEMBER 03: Italian Prime Minister Silvio Berlusconi leaves the conference centre after the first day of the G20 Summit on November 3, 2011 in Cannes, France. World's top economic leaders are attending the G20 summit in Cannes on November 3rd and 4th, and are expected to debate current issues surrounding the global financial system in the hope of fending off a global recession and finding an answer to the Eurozone crisis. (Photo by Dan Kitwood/Getty Images)

Volunteers try to keep alive some of the hundreds of stranded pilot whales after one of the country's largest recorded mass whale strandings, in Golden Bay, at the top of New Zealand's south island, February 10, 2017. Volunteers in New Zealand managed to refloat about 100 surviving pilot whales on Saturday, February 11, 2017 and are hoping they will swim back out to sea after more than 400 of the creatures swam aground at a remote beach. (Photo by Ross Wearing/Reuters)

Hugh Hefner spanks playboy models Izabella Kasprzyk and Bridget Marquardt during their birthday dinner party at Joya restaurant on September 25, 2002 in Beverly Hills, California. Playboy founder and sеxual revolution symbol Hugh Hefner has died at age 91. The magazine released a statement saying Hefner died at his home in Los Angeles of natural causes on Wednesday night, September 27, 2017, surrounded by family. (Photo by David Klein/Getty Images)

Chile's Javier Campillay drives past the burning car of Kazakhstan's Bauyrzhan Issabayev and Gabdulla Ashimov during the Dakar Rally 2014 Stage 2 from San Luis to San Rafael, on January 6, 2014. (Photo by Jean-Paul Pelissier/AFP Photo)

Bangladeshi fisherman feed their otters as they catch fish in Narail some 208 kms from Dhaka on March 11, 2014. The fishermen are using a rare technique that relies on coordination between man and trained otters, a centuries-old fishing partnership that has already long died out in other parts of Asia. (Photo by Munir Uz Zaman/AFP Photo)

A coil-shaped Helix Nebula showing a fine web of filamentary “bicycle-spoke” features embedded in the colorful red and blue ring of gas. At 650 light-years away, the Helix is one of the nearest planetary nebulae to Earth. A planetary nebula is the glowing gas around a dying, Sun-like star. (Photo by Reuters/NASA)