from turtle import*

color('yellow','yellow')

setup(0.5,0.5,0,0)

bgcolor("black")

begin_fill()

while True:

? ? forward(200)

? ? left(90)

? ? if abs(pos())<1:

? ? ? ? break

pensize(5)

color('red','yellow')

pendown()

forward(200)

left(90)

penup()

forward(200)

left(90)

pendown()

forward(200)

end_fill()

done()