Demonstrators help a fellow protester during clashes with security forces during an opposition rally in Caracas, Venezuela on April 4, 2017. Protesters clashed with police in Venezuela Tuesday as the opposition mobilized against moves to tighten President Nicolas Maduro' s grip on power. Protesters hurled stones at riot police who fired tear gas as they blocked the demonstrators from advancing through central Caracas, where pro- government activists were also planning to march. (Photo by Carlos Garcia Rawlins/Reuters)

The Royal Castle is seen a veil of heavy winter smog in Budapest, Hungary on January 30, 2017. (Photo by Laszlo Balogh/Reuters)

Elley Dann indulges in some sunbathing in Primrose Hill, London on June 24, 2020, after the UK officially recorded its warmest day of the year so far when the temperature reached 32.6C (90.7F) at London's Heathrow Airport at 2.46pm. (Photo by Evening Standard/The Sun)

Festival goers kiss in the “Silent Disco” at the “Music in the Park” stage during the 50th Montreux Jazz Festival, in Montreux, Switzerland, July 9, 2016. (Photo by Anthony Anex/EPA)

MTV “Ex On The Beach” star Charlotte Dawson and Big Brother star Sam Giffen (not pictured) having fun on a night out in Manchester, England after leaving neighbourhood restaurant on September 8, 2016. (Photo by XposurePhotos.com)

Lightning strikes the Willis Tower (formerly Sears Tower) in downtown on June 12, 2013 in Chicago, Illinois. (Photo by Scott Olson/Getty Images)

A Syrian refugee girl cries as she walks through a rainstorm towards Greece's border with Macedonia, near the Greek village of Idomeni, September 10, 2015. Most of the people flooding into Europe are refes fleeing violence and persecution in their home countries who have a legal right to seek asylum, the United Nations said on Tuesday. (Photo by Yannis Behrakis/Reuters)