Fix error in docstring
diff --git a/mako/ext/preprocessors.py b/mako/ext/preprocessors.py
index 94569c5..6be1d2d 100644
--- a/mako/ext/preprocessors.py
+++ b/mako/ext/preprocessors.py
@@ -15,6 +15,6 @@
     example:
  
     from mako.ext.preprocessors import convert_comments
-    t = Template(..., preprocessor=preprocess_comments)"""
+    t = Template(..., preprocessor=convert_comments)"""
     return re.sub(r'(?<=\n)\s*#[^#]', "##", text)