Lassana Bathily was an undocumented migrant from Mali until he became an unlikely hero by saving shoppers' lives during a jihadist attack on a Jewish supermarket in Paris a year ago. He has since been granted French citizenship by the President himself, been given new social housing, and a job at the Paris town hall. He's now studying and dreams of becoming a teacher. All part of a new life told in his book, which will be released on Wednesday.