The script makes gunicorn restart all the workers.

poke_gunicorn.py

#!/usr/bin/env python
# Sends HUP to the parent Gunicorn

import subprocess

for row in subprocess.check_output('ps axo ppid,pid,comm | grep gunicorn', shell=True).splitlines():
    parts = row.strip().split()
    if parts[0] == '1': # Parent
        subprocess.call(['kill', '-HUP', parts[1]])
        print 'gunicorn is now reloading your code.'
        break