A street vendor sells sliced fruits during a pro-government rally in Caracas, Venezuela, June 21, 2016. (Photo by Mariana Bazo/Reuters)

Expedition 44 flight engineer and NASA astronaut Scott Kelly seen inside the Cupola, a special module which provides a 360-degree viewing of the Earth and the International Space Station. Kelly is one of two crew members spending an entire year in space. (Photo by Scott Kelly/NASA)

Revellers attend the 25th edition of the Sziget Festival on August 9, 2017 in Budapest, Hungary. The Sziget Festival, one of the largest music and cultural festivals in Europe, celebrates its 25th anniversary in 2017, taking place from August 9-16 on the Hajogyari Sziget in Budapest. (Photo by Laszlo Mudra/Rockstar Photographers)

An injured young woman is led away after an incident at Parsons Green underground tube station in west London on September 15, 2017. Police and ambulance services said they were responding to an “incident” at Parsons Green underground station in west London on Friday, following media reports of an explosion. A Metro. co. uk reporter at the scene was quoted by the paper as saying that a white container exploded on the train and passengers had suffered facial burns. (Photo by Luke MacGregor/Reuters)

Riot police hold their weapons during a protest by supporters of Kenyan opposition National Super Alliance (NASA) coalition, along a street in Nairobi, Kenya on October 11, 2017. Opposition leader Raila Odinga, has called for protests this week, reiterated that he would not take part in a re- run of the presidential election on October 26, 2017 if his demands are not met, as Kenya' s Supreme Court last month overturned the August election of President Uhuru Kenyatta citing “irregularities” in the counting of results. (Photo by Thomas Mukoya/Reuters)

Policemen detain topless activists of women's rights group Femen, who stage a performance during a protest against Ukrainian President Petro Poroshenko and the government while marking the Day of Dignity and Freedom near the presidential administration headquarters in Kiev, Ukraine November 21, 2017. (Photo by Valentyn Ogirenko/Reuters)

A Sphynx cat at the 2017 Grand Prix Royal Canin international cat show at the Crocus Expo Exhibition Centre in Moscow, Russia on December 2, 2017. (Photo by Sergei Savostyanov/TASS/Barcroft Images)

School teachers and staff members take part during an active shooter training at James I. O'Neill High School in Highland Falls, New York, U.S., December 12, 2017. (Photo by Eduardo Munoz/Reuters)