import turtle
turtle.speed(0)

t = turtle.Turtle()
turtle.bgcolor("black")
turtle.speed(0)

for i in range(50):
    for colors in ["red","yellow","blue"]:
        turtle.color(colors)
        turtle.pensize(3)
        turtle.left(12)
        turtle.forward(200)
        turtle.left(90)
        turtle.forward(200)
        turtle.left(90)
        turtle.forward(200)
        turtle.left(90)
        turtle.forward(200)
        turtle.left(90)