diff --git a/docs/notebook_preamble.py b/docs/notebook_preamble.py
index a613ad5..bd1e220 100644
--- a/docs/notebook_preamble.py
+++ b/docs/notebook_preamble.py
@@ -29,20 +29,20 @@ S = ()
 
 
 def J(text, stack=S, dictionary=D):
-    print stack_to_string(run(text, stack, dictionary)[0])
+	print stack_to_string(run(text, stack, dictionary)[0])
 
 
 def V(text, stack=S, dictionary=D):
-    tp = TracePrinter()
-    try:
-        run(text, stack, dictionary, tp.viewer)
-    except:
-        exc = format_exc()
-        tp.print_()
-        print '-' * 73
-        print exc
-    else:
-        tp.print_()
+	tp = TracePrinter()
+	try:
+		run(text, stack, dictionary, tp.viewer)
+	except:
+		exc = format_exc()
+		tp.print_()
+		print '-' * 73
+		print exc
+	else:
+		tp.print_()
 
 
 define = lambda text: DefinitionWrapper.add_def(text, D)