From d951f6085bdd6109e2695eb370f731f14412cb23 Mon Sep 17 00:00:00 2001
From: "W. Trevor King" <wking@drexel.edu>
Date: Thu, 28 Jul 2011 13:48:20 -0400
Subject: [PATCH] Add _clear_class and _backed_subclasses to PackageConfig.

---
 pypiezo/config.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/pypiezo/config.py b/pypiezo/config.py
index 791c2e8..3f7bba8 100644
--- a/pypiezo/config.py
+++ b/pypiezo/config.py
@@ -34,6 +34,9 @@ class PackageConfig (_h5config_tools.PackageConfig):
         ]
 
 
+PackageConfig._clear_class = PackageConfig
+
+
 class AxisConfig (_config.Config):
     "Configure a single piezo axis"
     settings = [
@@ -105,3 +108,8 @@ class InputChannelConfig (ChannelConfig):
 
 
 _util.build_backend_classes(_sys.modules[__name__])
+
+PackageConfig._backed_subclasses = [
+    ('.h5', HDF5_PackageConfig),
+    ('.yaml', YAML_PackageConfig)
+    ]
-- 
2.26.2