def d(n,x,l,t):y=x[0]+l*math.sin(t),x[1]+l*math.cos(t);draw.aaline(c,(a[
u]+a[u+1]*n,a[u+2]+a[u+3]*n,a[u+4]),x,y);r=random.random;(display.flip()
,event.poll());n and[d(n-1,y,l*(.7+r()/5),t+i*r())for i in(-1,1)];2005.3
from pygame import*;import math,random,time;c=display.set_mode((800,600)
);u=time.localtime()[1]%12/3*5;s='winter','spring','summer','autumn';a=(
30,2.5,30,1,30,20,1.5,30,-.5,10,10,2,30,-.5,10,30,1,30,-.5,10);p=math.pi
while 1:c.fill((0,0,16));display.set_caption("tree: "+s[u/5]);draw.rect(
c,(32,)*3,(0,550,800,50));d(17,(400,550),100,p);u=(u+5)%20;time.sleep(3)
"Created by Kang Seonghoon <tokigun@gmail.com>; License: GNU LGPL ver 2"