<code>
# Use mmap to create pygame surfaces in files.

import mmap
import os

import pygame

width, height = 64,64
size = width * height * 3

test_file_name = "map_test.txt"

if not os.path.exist(test_file_name):
    f = open(test_file_name, "wb")
    f.close()

f = open(test_file_name, "r+")


# memory-map the file, size 0 means whole file
amap = mmap.mmap(f.fileno(), size, access=mmap.ACCESS_WRITE )

s = pygame.image.frombuffer(amap, (width,height), "RGB")

print s.get_at((0,0))
print s.set_at((0,0), (33,33,33,255))
</code>