Iraqi Shiite fighters from the Hashed al- Shaabi (Popular Mobilisation) paramilitaries hold a position near the village of Tal Abtah, south of Tal Afar, on November 30, 2016, during a broad offencive by Iraq forces to retake the city Mosul from Islamic State group jihadists. (Photo by Ahmad Al- Rubaye/AFP Photo)

Performers dressed as Ded Moroz, the equivalent of Santa Claus, and his granddaughter Snegurochka (Snow Maiden) take on shoe covers as they visit the Republican Scientific and Practical Centre of Pediatric Surgery in Minsk, Belarus, December 28, 2016. (Photo by Vasily Fedosenko/Reuters)

Danila Shmelev, an artist from Moscow, Russia, works on a 3-D picture in Dubai, United Arab Emirates, Monday, February 27, 2017. Artists who focus on 3-D pictures have gathered in Dubai for the Dubai Canvas 3-D Art Festival, which runs from March 1 through March 7. (Photo by Jon Gambrell/AP Photo)

A staff member sets up a ROBOTLEO robot at the Global Mobile Internet Conference (GMIC) 2017 in Beijing, China April 28, 2017. (Photo by Jason Lee/Reuters)

Festival goers dance during Glastonbury Festival at Worthy Farm, near Pilton, Somerset, Britain, 23 June 2017. The outdoor festival runs from 21 to 25 June. (Photo by Nigel Roddis/EPA)

A commuter exits a closed off station after a subway train derailment, Tuesday, June 27, 2017, in the Harlem neighborhood of New York. A subway train derailed near a station in Harlem on Tuesday, frightening passengers and resulting in a power outage as people were evacuated from trains along the subway line. The Fire Department of New York said a handful of people were treated for minor injuries at around 10 a.m. It said there was smoke but no fire. Delays were reported throughout the subway system. (Photo by Mary Altaffer/AP Photo)

People walk passed sculptures by Chinese artist Minjun Yue on a street outside a museum in Beijing, China on July 5, 2018. (Photo by Nicolas Asfouri/AFP Photo)

Children, some in tears, are escorted down a road in Barcelona, Spain, Thursday, August 17, 2017. Police in Barcelona say a white van has mounted a sidewalk, struck several people in the city's Las Ramblas district. (Photo by Manu Fernandez/AP Photo)