What does Mason think can be done about partisanship in our politics?

Lilliana Mason’s book is an attempt to argue that the roots of our contemporary political polarization are in social identities, not political identities. Drawing upon the long argument that she makes, please answer the following questions: what are the differences between social identities and political identities? What is political partisanship? How has political partisanship changed over time? How has social identity exacerbated partisanship far beyond what political identity could? When did social identity begin to enhance political partisanship and why did it happen at that point? What does Mason think can be done about partisanship in our politics?