[kupfer] Add BasicUnpickler to conspickle.py

[Ulrik Sverdrup <usverdrup src gnome org>]

commit 89a725868eb5d8ffc90a0dae79879dea2439b96d
Author: Ulrik Sverdrup <ulrik sverdrup gmail com>
Date:   Wed Feb 10 15:05:47 2010 +0100

    Add BasicUnpickler to conspickle.py

 kupfer/conspickle.py |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/kupfer/conspickle.py b/kupfer/conspickle.py
index 3d2a6f6..066f631 100644
--- a/kupfer/conspickle.py
+++ b/kupfer/conspickle.py
@@ -32,3 +32,12 @@ class ConservativeUnpickler (pickle.Unpickler):
 	def loads(cls, pickledata):
 		unpickler = cls(io.BytesIO(pickledata))
 		return unpickler.load()
+
+class BasicUnpickler (ConservativeUnpickler):
+	"An Unpickler that can only unpickle persistend ids and select builtins"
+	safe_modules = {
+		"__builtin__" : set(["object"]),
+		"copy_reg" : set(["_reconstructor"]),
+		"kupfer.puid" : set(["SerializedObject"]),
+	}
+