Design

 

from turtle import *

import colorsys

speed(0)

bgcolor('black')  

h=0.1

for i in range(150):

    c=colorsys.hsv_to_rgb(h,1,1)

    h+=0.1

    fillcolor(c)

    begin_fill()

    for j in range(3):

        fd(i)

        rt(120)

    circle(i,20)

    end_fill()

done()