where are the "class variables"?

[Dominik Kaspar]

i'm used to java and its strict way of defining variables. so how is
it possible to reach something like a class variable in python?
with the following code i didn't have much succes...

class Server(threading.Thread):
    running = 0  (??)
        
    def run(self):
        running = 1
        while running:
            print "do something here..."

    def exit(self):
        running = 0

thanks
-- dominik