Google Email Settings API - Enable IMAP for all users in your domain

I wrote the following python script to enable IMAP for all users in my Google App domain:

#! /usr/bin/env python

import gdata.apps.emailsettings.client
from gdata.client import BadAuthentication
from gdata.client import RequestError
import csv
import socket
if socket.gethostname() in ['trinh-pc',]: # add your hostname here
    from settings_local import *
    from settings import *
import sys

DOMAIN_ADMIN = 'domain_admin_username'
DOMAIN_ADMIN_P = 'domain_admin_password'

def get_username_list_from_text(username_file_path):
    # username_list = []
    text_file = open(username_file_path, 'rb')
    username_list =
    username_list = username_list.split('\n')
    return username_list

def create_gdata_client(domain, admin_email, admin_password, appname='GEM'):
        client = gdata.apps.emailsettings.client.EmailSettingsClient(domain=domain)
        client.ClientLogin(email=admin_email, password=admin_password, source=appname)
        return client
    except BadAuthentication, e:
        print "Create GDATA Client error: %s\n" % e

    return None

def enable_imap(client, username):
        client.UpdateImap(username=username, enable=True)
    except RequestError, e:
        print "Update IMAP for user %s error: %s\n" % (username, e)
def enable_imap_all(domain, admin_email, admin_password, username_list):
    client = create_gdata_client(domain, admin_email, admin_password)
    if client:
        for username in username_list:
            print "Enabling IMAP on username %s...\n" % username
            enable_imap(client, username)
            print "Finish enabling IMAP on username %s\n" % username
        print "Cannot create gdata client\n"

if __name__ == "__main__":
    username_file_path = sys.argv[1]
    username_list = get_username_list_from_text(username_file_path)
    if username_list:
        enable_imap_all(DOMAIN, DOMAIN_ADMIN, DOMAIN_ADMIN_P, username_list)

First, I need a text file contains all the users in my domain, each user per line.
Then, run the script:

$ ./ users.txt

The script uses gdata-python-client api to manipulate gdata api and email settings api: