gevent_example.py

from gevent import monkey; monkey.patch_all()
import gevent
import gevent.greenlet
from functools import partial
from random import random

import urllib
import urllib2

def on_exception(fun, greenlet):
    """Receiver in case of an error
    """
    print "Oops! Restarting..."
    fun()
    

def fetch_url(url):
    """Fetch an URL, sleep for some time and repeat. Die occasionally to emulate failure
    """
    while True:
        r = random()
        if r < 0.3:
            print "Raising an exception!"
            raise Exception("Time to die :(")
        data = urllib2.urlopen(url).read()
        print "Fetched %s..." % url
        gevent.sleep(r)


def main(urls):
    gs = [gevent.spawn(fetch_url, url) for url in urls]
    x = [g.link_exception(partial(on_exception, partial(main, urls))) for g in gs]
    gevent.joinall(gs)


if __name__ == '__main__':
    print main(["http://google.co.il", "http://google.com"])

x = [g.link_exception(partial(on_exception, main(urls)))) for g in gs]

Why not do like this?
Cause we have been sure that the main function won't have more args.

Sorry for my ignorance.
main(urls) is the result of the invoking of the main function rather than a callable object.