handle no qas or no predicates

app.py

@@ -1,7 +1,7 @@
 import gradio as gr
 import nltk
 from qanom.qanom_end_to_end_pipeline import QANomEndToEndPipeline
-
+from typing import List
 
 models = ["kleinay/qanom-seq2seq-model-baseline", 
           "kleinay/qanom-seq2seq-model-joint"]
@@ -26,10 +26,17 @@ def call(model_name, sentence, detection_threshold):
 
     pipeline = pipelines[model_name]
     pred_infos = pipeline([sentence], detection_threshold=detection_threshold)[0]
-    def pretty_pred_output(pred_info) -> str:
-        return "\n".join([f"{qa['question']} --- {';'.join(qa['answers'])}"
-                          for qa in pred_info['QAs']])
-    pretty_qa_output = "\n".join(pretty_pred_output(pred_info) for pred_info in pred_infos)
+    def pretty_qas(pred_info) -> List[str]:
+        if not pred_info or not pred_info['QAs']: return []
+        return [f"{qa['question']} --- {';'.join(qa['answers'])}"
+                for qa in pred_info['QAs']]
+    all_qas = [qa for pred_info in pred_infos for qa in pretty_qas(pred_info)]                      
+    if not pred_infos:
+        pretty_qa_output = "NO NOMINALIZATION FOUND"
+    elif not all_qas:
+        pretty_qa_output = "NO QA GENERATED"
+    else:
+        pretty_qa_output = "\n".join(all_qas) 
     # also present highlighted predicates
     positives = [pred_info['predicate_idx'] for pred_info in pred_infos] 
     def color(idx):