https://www.deviantart.com/barnababaruch/art/Rainbow-Circle-780241856
import math
try:
import tkinter
except ImportError:
import Tkinter as tkinter
def parabola(page, size):
for x in range(size):
y = x * x / size
plot(page, x, y)
plot(page, -x, y)
#Modify the circle function so that it allows the color of the circle to be specified
#and defaults to red if a color is not given.