Update LG_agent.py

LG_agent.py

@@ -3,20 +3,21 @@ from langgraph.graph.message import add_messages
 from langchain_core.messages import HumanMessage, AIMessage, AnyMessage
 from langgraph.prebuilt import ToolNode, tools_condition
 from langgraph.graph import START, StateGraph
-from langchain_google_genai import ChatGoogleGenerativeAI
+from langchain_openai import ChatOpenAI
 from tools import all_tools
 import os
 
 # 1. Setup once
-GOOGLE_API_KEY = os.getenv("GOOGLE_API_KEY")
-if not GOOGLE_API_KEY:
-    raise ValueError("Missing GOOGLE_API_KEY environment variable.")
+OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
+if not OPENAI_API_KEY:
+    raise ValueError("Missing OPENAI_API_KEY environment variable.")
 
-chat = ChatGoogleGenerativeAI(
-    model="gemini-1.5-flash",  # or "gemini-1.5-pro"
-    google_api_key=GOOGLE_API_KEY,
-    temperature=0
+chat = ChatOpenAI(
+    model="gpt-3.5-turbo",
+    openai_api_key=OPENAI_API_KEY,
+    temperature=0,
 )
+
 chat_with_tools = chat.bind_tools(all_tools)
 
 # 2. Define the agent state