[Zope] Python script to modify the permision on photos

[kbond]

Hello,

I have a very basic script  to write and I facing the some difficulties 
to understand the Zope Api.
My problem is the following :

I have tones of photo in several PhotoAlbums that do not have the 
correct permision.
I want to allow only a specific role to view those photos. I found out 
how to do it in interactive mode, using (instance:8080/manage), but with 
this method is way too  long so I have decided to write a script that 
will recursively change the permision on all the photo in a branch of my 
web site tree.

So far I already play around in "spe" and get the following:
++++++++++++++++++++++module++++++++++++++++++++++++++
#! /usr/bin/env python

import os, sys
sys.path.append("/usr/lib/zope/lib/python")
import Zope
Zope.configure("/home/yml/myZopeInstances/sitePerso/etc/zope.conf")
app = Zope.app()

#app.sitePerso.Albums.Photo_Album_la.get("Photo_Album.Apt")


------------------In 
Shell-------------------------------------------------------------
appart = app.sitePerso.Albums.Photo_Album_la.get("Photo_Album.Apt")
albumsChantier = appart.get("Photo_Album.chantier")
chant3 = albumsChantier.get("Photo_Album.chan3")
 >>>chant3.objectItems()

> [('Chantier 052.jpg', <Photo at 
> /sitePerso/Albums/Photo_Album_la/Photo_Album.Apt/Photo_Album.chantier/Photo_Album.chan3/Chantier 
> 052.jpg>), ('Chantier 053.jpg', <Photo at 
> /sitePerso/Albums/Photo_Album_la/Photo_Album.Apt/Photo_Album.chantier/Photo_Album.chan3/Chantier 
> 053.jpg>), ... cut.... ]


photo = chant3.get('Chantier 053.jpg')
photo.manage_permission("View", "MyRole",1)

I have several questions concerning this code:
How can I check, by script, that I have done a modification on the 
permission?
Please I am stuck And I do not know where to search I have googled the 
whole evening without any success.

Thank you for your help.