import pygame, sys
from pygame.locals import *

pygame.init()
DISPLAYSURF = pygame.display.set_mode((400,300))

mySurface = pygame.surface((50, 50))
mySurface.fill((0,255,0))

while True:
    for event in pygame.event.get():
        if event.type == QUIT:
            pygame.quit()
            sys.exit()
        pygame.display.update()