[Zope] [Python/Zope]how to open a "File"

[Rakotomandimby M. A.]

Hi all ,
I'm running Zope 2.6.2 (binary) on a Linux box.
I FTP-uploaded  to the server (into the Site root) a file named "foo".
The file has been added as a File Object ( no problem for that ) .
This file content a single line ended by a '\n' , wich is an IP address( 
no problem for that either )
I wrote a very simple python Script that should return the line inside 
that file _without_ the final '\n' :

import string
fichier = open('ancienne_ip','r')
ip = fichier.readline()
ip = string.strip(ip)
return ip

the problem is that i got error for this :

Error Type: NameError
Error Value: global name 'open' is not defined

What did i do wrong ?
Thnak you .