### Lesson 15: Turtle in the box

posted Feb 4, 2020, 8:00 AM by Attila Lengyel
 import turtle as tjohn = t.Turtle()john.shape("turtle")john.fillcolor("blue")john.pencolor("blue")screen = t.Screen()john.penup()john.setposition(-200,200)john.pendown()john.forward(400)john.right(90)john.forward(400)john.right(90)john.forward(400)john.right(90)john.forward(400)john.setposition(0,0)def geofence(): if john.ycor() > 190: return False if john.ycor() < -190: return False if john.xcor() > 190: return False if john.xcor() < -190: return False return Truedef move_forward(): speed = 10 if geofence() == False : john.setposition(0,0) john.pencolor("blue") john.forward(speed)def move_backward(): speed = 10 if geofence() == False : john.setposition(0,0) john.pencolor("white") john.backward(speed)def turn_right(): john.right(10)def turn_left(): john.left(10)def clear_screen(): john.clear()def start_draw(): john.pendown()def stop_draw(): john.penup()screen.onkey(move_forward, "Up")screen.onkey(move_backward, "Down")screen.onkey(turn_right, "Right")screen.onkey(turn_left, "Left")screen.onkey(clear_screen, "c")screen.onkey(stop_draw, "u")screen.onkey(start_draw, "d")screen.listen()