import turtle
s = turtle.Screen()
s.setup(420, 420)
SIZE = 400
half_size = SIZE/2
tx = turtle.Turtle()
tx.speed(0)
tx.up()
tx.goto(-half_size, -half_size)
tx.down()
tx.forward(SIZE)
ty = turtle.Turtle()
ty.speed(0)
ty.up()
ty.goto(-half_size, -half_size)
ty.down()
ty.left(90)
ty.forward(SIZE)
t1 = turtle.Turtle()
t2 = turtle.Turtle()
t3 = turtle.Turtle()
t1.color('red')
t2.color('green')
t3.color('blue')
t1.up()
t2.up()
t3.up()
t1.speed(0)
t2.speed(0)
t3.speed(0)
t1.goto(-half_size, -half_size)
t2.goto(-half_size, -half_size)
t3.goto(-half_size, -half_size)
t1.down()
t2.down()
t3.down()
for x in range(0, SIZE + 1, 10):
y1 = x / 10
y2 = x*x/1000
y3 = x*x*x/100000
t1.goto(x - half_size, y1 - half_size)
if y2 < SIZE:
t2.goto(x - half_size, y2 - half_size)
if y3 < SIZE:
t3.goto(x - half_size, y3 - half_size)