diff --git a/src/defaultKnownNodes.py b/src/defaultKnownNodes.py
index d4611099..f481581c 100644
--- a/src/defaultKnownNodes.py
+++ b/src/defaultKnownNodes.py
@@ -37,7 +37,7 @@ def createDefaultKnownNodes(appdata):
     #print stream1
     #print allKnownNodes
 
-    with open(appdata + 'knownnodes.dat', 'wb) as output:    
+    with open(appdata + 'knownnodes.dat', 'wb') as output:
         # Pickle dictionary using protocol 0.
         pickle.dump(allKnownNodes, output)