colorful_brownian_motion.py

from Tkinter import Tk, Canvas
import random

canvas_size = 500
x = 250
y = 250
delay = 10
colors = ["red","orange","yellow","green","blue","cyan","magenta","light blue"]

def step():
  global x, color,y,i
  i+=1
  if i%30==0:
      color=colors[i%8]
  x += random.randint(-3, 3)
  y += random.randint(-3, 3)
  canvas.create_line([x, y], [x + 3, y], fill=color,width=16)
  root.after(delay, step)

i=0
color='black'
root = Tk()
canvas = Canvas(root, width=canvas_size, height=canvas_size, background='black')
canvas.pack()
step()
root.mainloop()