diff --git a/Lib/lib2to3/fixes/fix_unicode.py b/Lib/lib2to3/fixes/fix_unicode.py
index c7982c2b97c3e1c..425c3250bb75716 100644
--- a/Lib/lib2to3/fixes/fix_unicode.py
+++ b/Lib/lib2to3/fixes/fix_unicode.py
@@ -36,7 +36,7 @@ def transform(self, node, results):
             if val[0] in 'uU':
                 val = val[1:]
             if val == node.value:
-                return node
+                return None
             new = node.clone()
             new.value = val
             return new
diff --git a/Lib/lib2to3/pytree.py b/Lib/lib2to3/pytree.py
index 2a6ef2ef5240a2b..08861af3f2a6440 100644
--- a/Lib/lib2to3/pytree.py
+++ b/Lib/lib2to3/pytree.py
@@ -115,11 +115,12 @@ def replace(self, new):
             else:
                 l_children.append(ch)
         assert found, (self.children, self, new)
-        self.parent.changed()
-        self.parent.children = l_children
+		parent = self.parent
+		self.parent = None
+        parent.children = l_children
         for x in new:
-            x.parent = self.parent
-        self.parent = None
+            x.parent = parent
+        parent.changed()
 
     def get_lineno(self):
         """Return the line number which generated the invocant node."""