diff --git a/Tools/compiler/astgen.py b/Tools/compiler/astgen.py
index 0156567..4ccc54d 100644
--- a/Tools/compiler/astgen.py
+++ b/Tools/compiler/astgen.py
@@ -283,4 +283,4 @@
 ### EPILOGUE
 for name, obj in globals().items():
     if isinstance(obj, type) and issubclass(obj, Node):
-       nodes[name.lower()] = obj
+        nodes[name.lower()] = obj