# Recipe 49: Draw the picture in Figure 5.16

def coolpic():

  canvas=makeEmptyPicture(250, 250) #make an empty picture
  blueval = 10 #a color value for blue
  for index in range(25,1,-1): #loop in reverse from 25 to 1
    color = makeColor(index*10,index*5,blueval) #make a color based on loop position
    addRectFilled(canvas,index*5,index*5,index*10,index*10,color) #create a filed rectangle in the picture with dimensions and position based on loop position
    blueval = blueval + 10 #increment the blue color value
    
  show(canvas)
  return canvas