Update langgraph_agent.py

langgraph_agent.py

@@ -76,7 +76,7 @@ tools = [
 ]
 
 
-with open("system_prompt.txt", "r", encoding="utf-8") as f:
+with open("prompt.txt", "r", encoding="utf-8") as f:
     system_prompt = f.read()
 sys_msg = SystemMessage(content=system_prompt)