fixed class label feature set for re-tacred

tacred.py

@@ -285,7 +285,7 @@ class Tacred(datasets.GeneratorBasedBuilder):
                 "stanford_ner": datasets.Sequence(datasets.Value("string")),
                 "stanford_deprel": datasets.Sequence(datasets.Value("string")),
                 "stanford_head": datasets.Sequence(datasets.Value("int32")),
-                "relation": datasets.ClassLabel(names=_CLASS_LABELS),
+                "relation": datasets.ClassLabel(names=_RETACRED_CLASS_LABELS if self.config.name == 're-tacred' else _CLASS_LABELS),
             }
         )