What do you think of the following innocuous Python code ?

from gevent import monkey  
monkey.patch_all(thread=False, select=False)  
import requests

requests.get('http://i-do-not-exist.com')  
print('THIS WILL NEVER BE PRINTED !!!')  

Guess what ? The string message will never get printed :(

Simply remove the monkey.patch_all line and you'll get a pretty socket.gaierror: [Errno 8] Name or service not known.

I tested this with gevent==1.2.1 and Windows 10, with the gevent & greenlet packages built from source by pip install.