deadlock.py

from itertools import count
import gevent
from gevent.event import AsyncResult


def wait_twice(async_result):
    print('wait_twice enter')
    gevent.joinall([async_result, async_result], raise_error=True)
    print('wait_twice exit')


def set_result(async_result):
    print('set_result enter')
    async_result.set(1)
    print('set_result exit')


def go_for_ever():
    print('go_for_ever enter')
    for i in count():
        print(i)
        gevent.sleep(.1)
    print('go_for_ever exit')


g = gevent.spawn(go_for_ever)
result = AsyncResult()
gevent.wait([
    gevent.spawn(wait_twice, result),
    gevent.spawn(set_result, result),
])