set the initial exports to contents of the exports file when calculating
the inventory
diff --git a/reclass/core.py b/reclass/core.py
index afdcf40..c962c74 100644
--- a/reclass/core.py
+++ b/reclass/core.py
@@ -164,8 +164,8 @@
 
     def inventory(self):
         original_exports = Parameters(self._storage.get_exports())
+        exports = copy.deepcopy(original_exports)
         original_exports.render_simple()
-        exports = Parameters()
         entities = {}
         for n in self._storage.enumerate_nodes():
             entities[n] = self._nodeinfo(n, exports)