People pause at a memorial set up for victims of a mass shooting in Las Vegas, Nev., on Tuesday, October 3, 2017. A gunman opened fire on an outdoor music concert on Sunday. It was the deadliest mass shooting in modern U.S. history, with dozens of people killed and hundreds injured, some by gunfire, some during the chaotic escape. (Photo by John Locher/AP Photo)

An elderly woman plays an accordion in Moscow, Russia on October 3, 2017. (Photo by Mladen Antonov/AFP Photo)

This photo taken on October 8, 2017 shows dancers posing in formation to celebrate the upcoming Party Congress, in Rongan in China' s southern Guangxi region. China will convene its 19 th Party Congress on October 18, state media said, a key meeting held every five years where President Xi Jinping is expected to receive a second term as the ruling Communist Party' s top leader. (Photo by AFP Photo/Stringer)

In this Thursday, October 5, 2017 photo, Chile's singer-songwriter Mon Laferte performs in concert at the Auditorio Nacional in Mexico City. The 34-year-old artist, who just received five Latin Grammy nominations, performed three sold-out concerts at the National Auditorium, on consecutive evenings, beginning Thursday. (Photo by Eduardo Verdugo/AP Photo)

Vocalist Laila Skovmand, a musician with Danish company Between Music, plays underwater in a tank during a rehearsal ahead of their UK premiere concert Aquasonic at the Tramway in Glasgow on Ocrober 25, 2017. (Photo by Robert Perry/PA Images)

A visitor jumps for a photograph on the world's highest and longest glass-bottomed bridge above a valley in Zhangjiajie in China's Hunan Province on August 21, 2016. The bridge, which opened to the public on a trial basis on Saturday, spans 430 meters (1,410 feet) and rises about 300 meters (984 feet) above a valley in a scenic zone, making it the world's highest and longest glass-bottomed bridge according to Chinese state media. (Photo by Fred Dufour/AFP Photo)

A Muslim woman wearing a Hijab kicks the water in the Mediterranean Sea as a woman wearing a bikini stands nearby at the beach in Tel Aviv, Israel August 30, 2016. (Photo by Baz Ratner/Reuters)

Costumed characters participate in the 30th annual Dragon Con Parade in Atlanta, Georgia, USA, 03 September 2016. Thousands of attendees crowd downtown Atlanta hotels and streets during the Labor Day weekend for the Dragon Con science fiction and fantasy convention, many dressed as their favorite characters. (Photo by Erik S. Lesser/EPA)