Mohsin Hamid has been called one of the most talented and inventive writers of his generation. His books "Moth Smoke" and "The Reluctant Fundamentalist" have both been adapted for the screen - they explore the changes overtaking our world. His latest novel "Exit West" was cited by Barack Obama as one of the best books he read in 2017. As it comes out in French, the author speaks to Eve Jackson about tackling the migrant crisis in his new work, Donald Trump's travel ban and how mass migration will change the world for the better.