Sultana announced on Thursday she was quitting Labour to join Jeremy Corbyn’s Independent AllianceJohn McDonnell, independent MP for Hayes and Harlington and former shadow chancellor for Labour from 2015 to 2020, said Labour needs to “ask themselves” why someone like Zarah Sultana would choose to leave.This comes after Sultana, MP for Coventry South, announced she is resigning from the party to join Jeremy Corbyn’s Independent Alliance.The people running Labour at the moment need to ask themselves why a young, articulate, talented, extremely dedicated socialist feels she now has no home in the Labour party and has to leave.Politics isn’t just