Code in Unit 6.2 section will not compile due to x_position being private

Course Support C++ For Robotics
1 
Code below from section "Accessing attributes and methods: the dot ." in Unit 6.2 needs one change. first_robot.x_position should be changed to first_robot.set_position(1.15) so that a method reaches the private member x_position;



   Robot first_robot;

first_robot.name = "Fastbot";      // set an attribute
first_robot.x_position = 1.15;
first_robot.battery = 90;

first_robot.print_name();          // call a method