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Changes between Version 2 and Version 3 of Ticket #17232, comment 2

-              v2
+              v3
                     cache.append((field, parent))
         cache.extend([(f, None) for f in self.local_fields])
         # Original line
+        # Original lines
         #self._field_cache = tuple(cache)
+        #self._field_name_cache = [x for x, _ in cache]
         # Second feeble attempt to avoid duplicates