This program creates eight green spheres located at the corners of a cube. Extend the program by putting all eight spheres in a list. Then write a loop to turn the spheres magenta one by one. There should only be three lines of code inside your while loop: a rate statement, the line that changes the color of a sphere, and the line that updates the loop index. Use rate of $1$ so you can see the spheres change color one by one."