# Just for variety...
import turtle as t
from math import *

# Reminder: 
# Import everything FROM the library
# from turtle import *
# Import turtle library (as turtle)
# import turtle

def limit_sin(n):
    return 0.5 + sin(n)/2

t.pensize(4)
t.speed(0)
color_factor = 0
while True:    
    t.color((limit_sin(color_factor), limit_sin(color_factor / 4), 1 - limit_sin(color_factor)))
    t.circle(200)
    t.left(28)
    color_factor += .1