clear()
setPenThickness(10)
forward(10)
setPenThickness(10)
forward(10)
setPenThickness(15)
forward(10)
setPenThickness(20)
forward(10)
setPenThickness(25)
forward(10)
setPenThickness(30)
forward(10)
setPenThickness(40)
forward(10)
setPenThickness(45)