fix for ValueError below

raise ValueError(

ValueError: Examples must be a list of lists when additional inputs are provided.

app.py

@@ -151,7 +151,7 @@ with gr.Blocks(title="PDF Chatbot") as demo:
         fn=chat_with_pdf,
         chatbot=gr.Chatbot(type="messages"),
         textbox=gr.Textbox(placeholder="Type your question here...", scale=7),
-        examples=["What is the main topic of the document?", "Summarize the key findings.", "Who are the authors?"],
+        examples=[["What is the main topic of the document?"], ["Summarize the key findings."], ["Who are the authors?"]],
         title="Chat Interface",
         theme="soft",
         # Fix: Add the state as an additional input to the ChatInterface