added error handling for the attribute error to restart state machine

app.py

@@ -32,17 +32,32 @@ def generate_questions(
     if not taxonomy or len(taxonomy) == 0:
         msg = "Choose at least one taxonomy."
         raise gr.Error(msg)
-    machine.value.send(
-        "process_event",
-        event_={
-            "type": "user_input",
-            "value": {
-                "page_range": (page_lower, page_higher),
-                "question_number": question_number,
-                "taxonomy": taxonomy,
+    try:
+        machine.value.send(
+            "process_event",
+            event_={
+                "type": "user_input",
+                "value": {
+                    "page_range": (page_lower, page_higher),
+                    "question_number": question_number,
+                    "taxonomy": taxonomy,
+                },
             },
-        },
-    )
+        )
+    except AttributeError:
+        create_statemachine()
+        machine.value.start_machine()
+        machine.value.send(
+            "process_event",
+            event_={
+                "type": "user_input",
+                "value": {
+                    "page_range": (page_lower, page_higher),
+                    "question_number": question_number,
+                    "taxonomy": taxonomy,
+                },
+            },
+        )
     return (
         "## Questions Ready for Download Below",
         gr.update(