--- storage.py	2009-11-13 17:47:25.000000000 +0800
+++ storage.py	2009-11-15 15:51:49.000000000 +0800
@@ -80,6 +80,12 @@
         for (k, v) in value.items():
             self[k] = v
 
+    def copy(self):
+        self_ = Storage()
+        for k in self.keys():
+            self_[k] = self[k]
+        return self_
+
 
 def load_storage(filename):
     fp = open(filename, 'rb')