import sys
sys.stdout.write(open('penguin.png', 'rb').read())
NO. NO. NO.sys.stdout is a global variable. If you want sys.stdout.write() to end up in the user's terminal, your web server will be able to either serve only one request at a time, or must be forced into running separate processes for each concurrent request (which will not happen on windows and many other supported platforms).
We made that mistake with cgipython, and we won't make it again. Learn from the mistakes of others, as you do not have the time to make them all yourself.
Mike
