Here is a newer one: https://github.com/shaunduncan/smokesignal. "smokesignal is a simple python library for sending and receiving signals. It draws some inspiration from the django signal framework but is meant as a general purpose variant." Example:
from time import sleep
import smokesignal
@smokesignal.on('debug')
def verbose(val):
print "#", val
def main():
for i in range(100):
if i and i%10==0:
smokesignal.emit('debug', i)
sleep(.1)
main()