Update app.py

app.py

@@ -69,7 +69,7 @@ if input:
         
                 bot_answer = random.choice(response_templates)
                 message_history.append({"text":bot_answer, "is_user" : False})
-        if key_exists = False:
+        if key_exists == False:
             fallback_template = ["I didn't get the question 🧐 Could you please ask again? Try 'What should I use for detecting masks in an image?'",
                                      "Hmm, not sure I know the answer, maybe you could ask differently? 🤓",
                                      "Sorry, I didn't understand you, maybe you could ask differently? 🤓 Try asking 'What should I use to extract name in a document' 🤗"]