There’s an old saying that all politics is local, and few know that better than Michael Nutter. He served almost 15 years on the Philadelphia City Council before being elected as the city’s mayor, a position he held for two terms. Nutter, a Democrat, left public office in 2016 and now serves as an executive fellow at Penn’s School of Social Policy and Practice and professor at Columbia University. He’s also written a book about his tenure leading America’s sixth-largest city, titled Mayor: The Best Job in Politics . He talked about his book on the Knowledge at Wharton radio show on  Wharton Business Radio, which airs on SiriusXM . An edited transcript of the conversation follows. Knowledge at Wharton: Why do you believe mayor is the best job in politics? Michael Nutter: You can get things done, make things happen.…