A student protester throws a stone against a riot police vehicle during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)

A woman mourns over the coffin of a relative after a deadly eruption of Mount Sinabung in Sukandebi village, Karo, North Sumatra, Indonesia May 22, 2016, in this photo taken by Antara Foto. The volcano in western Indonesian unleashed hot clouds of ash on Saturday, killing several villagers, an official said. (Photo by Irsan Mulyadi/Reuters/Antara Foto)

U.S. Secretary of State John Kerry and Mongolian Foreign Minister Lundeg Purevsuren watch an archer during a Naadam ceremony, a competition which traditionally includes horse racing, Mongolian wrestling and archery, in Ulan Bator, Mongolia, June 5, 2016. (Photo by Saul Loeb/Reuters)

A labourer carries a basket of bananas inside a wholesale fruit and vegetable market in Bengaluru, India, August 22, 2016. (Photo by Abhishek N. Chinnappa/Reuters)

A model on a wheelchair presents creations by designer Takafumi Tsuruta from his Spring/Summer 2016 collection for his brand Tenbo, during Tokyo Fashion Week in Tokyo, Japan, October 13, 2015. (Photo by Yuya Shino/Reuters)

A model checks her mobile phone backstage during Kazakhstan Fashion Week in Almaty, Kazakhstan, October 14, 2015. (Photo by Shamil Zhumatov/Reuters)

A model attends a fashion show at the “German Fetish Ball” in Berlin, Germany on May 12, 2018. (Photo by Hannibal Hanschke/Reuters)

A woman touches a robot at the 2018 World Robot Conference in Beijing on August 15, 2018. The conference will be held from 15 to 19 August and will include a conference on robotics, an exhibition and a robot competition with the participation of robotics enterprises to showcase their robot products. (Photo by Wang Zhao/AFP Photo)