acknowledgments xxv introduction xxvii whom is this book forxxviii conventions xxviii what is programmingxxix what is pythonxxx programmers don' need to know much math xxx you are not too old to learn programming xxxi programming is creative activity xxxi about this book xxxi downloading and installing python xxxiii downloading and installing mu xxxiv starting mu xxxiv starting idle xxxv the interactive shell xxxv installing third-party modules xxxvi how to find help xxxvi asking smart programming questions xxxviii summary xxxix part ipython programming basics python basics entering expressions into the interactive shell the integerfloating-pointand string data types string concatenation and replication storing values in variables assignment statements variable names your first program dissecting your program comments the print(function the input(function printing the user' name the len(function the str()int()and float(functions summary practice questions