Three years ago, the Iranian singer and composer Sara Najafi came up with the idea of hosting a concert in Tehran, her hometown. It was a plan so audacious, it seemed slightly nuts. The concert would be “a festival of the female voice” featuring solo singers – not just Iranians, but artists from France and Tunisia, too. Nothing like it had been attempted in Iran for 35 years: after the Islamic Revolution of 1979, women were banned from singing solo in public. What’s more, Sara was inspired by the Green Movement, which grew out of the mass protests at Iran’s 2009 presidential elect