From db60ba1facbcdd730f21acce5f2b1a8056a4564d Mon Sep 17 00:00:00 2001
From: Shy <shy@koeln.ccc.de>
Date: Fri, 31 Mar 2017 17:14:03 +0200
Subject: [PATCH] Missing master is now None, not empty string

---
 c4ctrl.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/c4ctrl.py b/c4ctrl.py
index d3eae0e..99eec80 100755
--- a/c4ctrl.py
+++ b/c4ctrl.py
@@ -340,7 +340,7 @@ class Keller(C4Room):
             ("Innen", "licht/keller/innen"),
             ("Vorne", "licht/keller/vorne")
         )
-    master = ""
+    master = None
     lights = ()