import turtle
turtle.bgcolor("black")
t= turtle.Turtle()
s = turtle.Screen()
t.pencolor("green")
a=0
b=0
t.speed(0)
t.goto(0,200)
while True:
    t.forward(a)
    t.right(b)
    a+=3
    b+=1
    if b==210:
        break

turtle.done()
