TOPSHOT - Riot police use a water cannon against protesters after the &#39;Welcome to Hell&#39; rally against the G20 summit in Hamburg, northern Germany on July 6, 2017. Leaders of the world&#39;s top economies will gather from July 7 to 8, 2017 in Germany for likely the stormiest G20 summit in years, with disagreements ranging from wars to climate change and global trade. / AFP PHOTO / Christof STACHE