I don't know why this Python Programming code doesn't work
<pre><code>import pygame, sys 
from pygame.locals import *

pygame.init() 
screen=pygame.display.set_mode((640,360),0,32) 

while True:     
    for event in pygame.event.get():        
        if event.type == QUIT:          
            pygame.quit()           
            sys.exit()          
        screen.lock()           
        pygame.draw.rect(screen, (140,240,130), Rect((100,100),(130,170)))
        screen.unlock()     
        pygame.display.update()
</code></pre>

<p>It's supposed to show a retangle in a 640x360 window, and it doesn't do that, and I don't know why it doesn't do that. Please help me. </p>
