title: Pygame Surface.fill() not working
body: <p>I recently started learning pygame. I made a very basic program (all it does is change it's own background colour):</p>
  
  <pre><code>import pygame
  from pygame.locals import *
  
  pygame.init()
  DISPLAY = pygame.display.set_mode((800,600))
  
  
  while True:
      for event in pygame.event.get():
          if event == QUIT:
              pygame.quit()
              sys.exit()
      DISPLAY.fill((3,4,5))
      pygame.display.update()
  </code></pre>
  
  <p>yet when the program ran all it did was produce a blank, black pygame window. I am using Windows 10 64-bit home with python 3.5.2 and pygame 1.9.1. Please help me figure out why the program didn't work?</p>