Fixed issues added comments correctly

app.py

@@ -13,7 +13,7 @@ from dotenv import load_dotenv
 
 load_dotenv()
 
-=== CONFIG ===
+#=== CONFIG ===
 
 STORAGE_DIR = "storage"
 CLEANUP_INTERVAL = 600  # 10 min
@@ -24,7 +24,7 @@ OPENROUTER_MODEL = "z-ai/glm-4.5-air:free"
 if not os.path.exists(STORAGE_DIR):
 os.makedirs(STORAGE_DIR)
 
-=== CLEANUP THREAD ===
+#=== CLEANUP THREAD ===
 
 def cleanup_old_sessions():
 while True:
@@ -37,7 +37,7 @@ time.sleep(CLEANUP_INTERVAL)
 
 Thread(target=cleanup_old_sessions, daemon=True).start()
 
-=== PDF PROCESSING ===
+#=== PDF PROCESSING ===
 
 def process_pdf(pdf_file):
 if pdf_file is None:
@@ -59,7 +59,7 @@ db.save_local(session_path)
 chat_history = [("System", "Paper uploaded and processed. You can now ask questions.")]  
 return f"Paper uploaded successfully. Session ID: {session_id}", session_id, chat_history
 
-=== QUERY FUNCTION ===
+#=== QUERY FUNCTION ===
 
 def query_paper(session_id, user_message, chat_history):
 if not session_id or not os.path.exists(os.path.join(STORAGE_DIR, session_id)):
@@ -115,7 +115,7 @@ chat_history.append((user_message, answer))
   
 return chat_history, ""
 
-=== GRADIO UI ===
+#=== GRADIO UI ===
 
 with gr.Blocks() as demo:
 gr.Markdown("## 📄 Research Paper Chatbot (RAG + OpenRouter)")