from florida on a mission to produce an enormous sd map of the cosmos. now on bbc news — political thinking with nick robinson. hello and welcome to political thinking. if, and it is a mighty big if, keir starmer makes it to number 10, the route to downing street will have to run through scotland. labour will have to win votes and votes in big numbers in the original red wall, in those once heartlands for the party north of the border. now, they have just one member of parliament. my guest on political thinking this week is labour's scottish leader, anas sarwar.