subprocess leaves child living - comp.lang.python

Message from discussion subprocess leaves child living
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From: Thomas Dybdahl Ahle <lob...@gmail.com>
Subject: subprocess leaves child living
Newsgroups: comp.lang.python
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Hi, When I do a small program like

from subprocess import Popen
popen = Popen(["ping", "google.com"])
from time import sleep
sleep(100)

start it and kill it, the ping process lives on.
Is there a way to ensure that the ping process is always killed when the 
python process is?
I can't use atexit, as ping then isn't killed when python is killed "in 
the hard way"