diff --git a/lib/facter/odoo.rb b/lib/facter/odoo.rb
index 0bc8438..76de48f 100644
--- a/lib/facter/odoo.rb
+++ b/lib/facter/odoo.rb
@@ -53,7 +53,7 @@ def module_info(addon):
               env = odoo.api.Environment(cr, uid, ctx)
 
               res['databases'][dbname] = {}
-              regex = re.compile('\\A__\\w*__\\Z')
+              regex = re.compile(r'\\A__\\w*__\\Z')
               res['databases'][dbname]['addons'] = {}
               for addon in dir(odoo.addons):
                   if not regex.match(addon):