Add missing comma.

pydemo/euler/main.py

@@ -29,5 +29,5 @@ parameters = {"fem.ode.odesolver": "EX",
 run(*problem(),
         startLevel=0, polOrder=2, limiter="default",
         primitive=primitive, saveStep=0.1, subsamp=2,
-        dt=None,threading=True,grid="alucube", space="dgonb"
+        dt=None,threading=True,grid="alucube", space="dgonb",
         parameters=parameters)