import threading, sys, time

class MyThread(threading.Thread):
    def run(self):
        # create a file, so that when the main thread clears 
        # all threads states, file.close() is called, which 
        # releases the GIL and gives a chance to the loop below 
        # to execute again.
        f = open("c:/temp/@temp", "w")

        while True:
            time.sleep(0)
            time.sleep

t = MyThread()
t.setDaemon(True)
t.start()
time.sleep(0.01)