A Iraqi soldier of the 9th division is seen within a Humvee in Shyma district in Mosul, Iraq, Tuesday, December 6, 2016. Iraqi forces, backed by the U.S.-led international coalition, launched a campaign in October to retake Mosul, the country's second largest city and IS's last major urban bastion in Iraq. (Photo by Manu Brabo/AP Photo)

Seized plastic handguns which were created using 3D printing technology are displayed at Kanagawa police station in Yokohama, south of Tokyo, in this photo taken by Kyodo May 8, 2014. Yoshimoto Imura became the first man to be arrested in Japan for illegal possession of two guns he created himself using 3D printing technology, Japanese media said on Thursday. The 27-year-old, a college employee in the city of Kawasaki, was arrested after police found video online posted by Imura claiming to have produced his own guns. Gun possession is strictly regulated in Japan. Police raided Imura's home and found five guns, two of which could fire real bullets, Japanese media said. (Photo by Reuters/Kyodo)

Alex Plunkett, left, and Sean Hart, both of Arlington, Va., join hundreds participating in the annual International Pillow Fight Day on April 5. Massive pillow fights broke out on the Mall in Washington and in cities around the world. (Photo by Marvin Joseph/The Washington Post)

A picture made available on 09 September 2015 shows traditional mud men dancers from the Asaro District of Goroka in the Eastern Highlands Province of Papua New Guinea perform for the official opening of the Pacific Islands Forum in Port Moresby, Papua New Guinea, 08 September 2015. The Pacific Islands Forum goes from 07 to 11 September and discusses the regions vulnerability to Climate Change. (Photo by Mick Tsikas/EPA)

Demonstrators depicting Brazil's former President Luiz Inacio Lula da Silva (R) and Brazil's President Dilma Rousseff attend a protest against Rousseff, part of nationwide protests calling for her impeachment, in Brasilia, Brazil, March 13, 2016. (Photo by Ueslei Marcelino/Reuters)

One of four Acehnese teen gets whipped for spending time in close proximity with her boyfriend who is not her husband, which is against Sharia law, in Aceh on April 18, 2017. Aceh on Sumatra island began implementing Sharia law after being granted special autonomy in 2001, an attempt by the central government in Jakarta to quell a long-running separatist insurgency. (Photo by Chaideer Mahyuddin/AFP Photo)

A group of fashionable nonagenarians pose for a photo in Pengzhou, Sichuan, China on October 12, 2016. (Photo by Rex Features/Shutterstock)

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)