gevent.py

from gevent import spawn, sleep


def g1():
    print "g1 enter"
    spawn(g2)
    print "g1 exit"


def g2():
    while True:
        print "g2 still there"
        sleep(0.5)

# does not work since the return of spawn() falls off stack
def run():
   spawn(g1)
   
run()
sleep(10.0)