Update app.py

app.py

@@ -162,7 +162,7 @@ def perform_aste_inference(text, dataset):
     result = triplet_extractor.predict(text)
 
     pred_triplets = pd.DataFrame(result["Triplets"])
-    true_triplets = pd.DataFrame(result["True Triplets"])
+    true_triplets = pd.DataFrame(result["True Triplets"]) if result["True Triplets"] else None
     return pred_triplets, true_triplets, "{}".format(text.split("####")[0])