minimal documentation on how to override a generated getter on the class

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@10381 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/Accessor/Base.py

@@ -108,8 +108,14 @@ evaluateTales = CachingMethod(_evaluateTales, id = 'evaluateTales', cache_durati
 
 class Getter(Method):
     """
-      Gets an attribute value. A default value can be
-      provided if needed
+      Gets an attribute value. A default value can be provided if needed.
+
+    Note that 'default' argument is the first positional argument, this is
+    important if you want to override a Getter in a class,  overloaded
+    accessors have to respect this::
+
+      getSomething(self, [default], [name=value, [name=value], ])
+
     """
     _need__name__=1