Update rag_langgraph.py

rag_langgraph.py

@@ -130,5 +130,4 @@ def create_graph(topic, word_count):
 
 def run_multi_agent(topic, word_count):
     graph = create_graph(topic, word_count)
-
-    return graph.invoke(new HumanMessage("Code hello world and print it to the terminal"))
+    result = graph.invoke({"question": "Code hello world and print it to the terminal"})