diff --git a/libsaria/trees.py b/libsaria/trees.py
index 170604dd..af275873 100644
--- a/libsaria/trees.py
+++ b/libsaria/trees.py
@@ -226,8 +226,16 @@ class PersPrefTree(PrefTree):
 
 	def init_pref(self, pref, value):
 		PrefTree.init_pref(self, pref, value)
-		data.save(self.file, ".tree")
+		if self.file != None:
+			data.save(self, self.file, ".tree")
 
 	def set_pref(self, pref, value):
 		PrefTree.set_pref(self, pref, value)
-		data.save(self.file, ".tree")
+		if self.file != None:
+			data.save(self, self.file, ".tree")
+
+def get_pref_tree(file):
+	tree = data.load(file, ".tree")
+	if tree == None:
+		tree = PersPrefTree(file)
+	return tree