diff --git a/Demo/parser/unparse.py b/Demo/parser/unparse.py
index 9ec9deb9d5c..7acc05d93f4 100644
--- a/Demo/parser/unparse.py
+++ b/Demo/parser/unparse.py
@@ -10,7 +10,7 @@ def interleave(inter, f, seq):
     seq = iter(seq)
     try:
         f(seq.next())
-    except StopIteration: 
+    except StopIteration:
         pass
     else:
         for x in seq: