Update src/chatbot.py

src/chatbot.py

@@ -17,20 +17,19 @@ logger = logging.getLogger(__name__)
 from langchain.callbacks.base import BaseCallbackHandler
 
 class StreamHandler(BaseCallbackHandler):
-    def __init__(self, placeholder):
+    def __init__(self, placeholder=None):
         self.current_text = ""
         self.placeholder = placeholder
 
     def on_llm_new_token(self, token: str, **kwargs):
         self.current_text += token
-        # Update Streamlit UI live
-        self.placeholder.markdown(self.current_text + "▌")
+        if self.placeholder:
+            self.placeholder.markdown(self.current_text + "▌")
 
     def get_text(self):
         return self.current_text
 
 
-
 class BioethicsChatbot:
     def __init__(self, data_dir: str="data/sample_papers"):
         self.processor = DocumentProcessor()