Update agent.py

agent.py

@@ -1,32 +1,37 @@
-# agent.py  –  LangChain · LangGraph · Gemini Flash
-# ================================================
-
-"""
-Abhängigkeiten (requirements.txt):
-----------------------------------
-langchain==0.1.*
-langgraph
-google-generativeai
-tavily-python
-wikipedia-api
-pandas
-openpyxl
-tabulate
-"""
-
-import os, re, time, functools
+import os
+import re
+import time
+import functools
 from typing import Dict, Any, List
 
 import pandas as pd
+
+# LangGraph
 from langgraph.graph import StateGraph, START, END, MessagesState
 from langgraph.prebuilt import ToolNode, tools_condition
 
-from langchain_google_genai import ChatGoogleGenerativeAI
+# LangChain Core
 from langchain_core.messages import SystemMessage, HumanMessage
 from langchain_core.tools import tool
+
+# Google Gemini
+from langchain_google_genai import ChatGoogleGenerativeAI
+
+# Tools
 from langchain_community.tools.tavily_search import TavilySearchResults
 from langchain_community.utilities.wikipedia import WikipediaAPIWrapper
-from langchain_experimental.tools.python.tool import PythonAstREPLTool
+
+# Python REPL Tool
+try:
+    from langchain_experimental.tools.python.tool import PythonAstREPLTool
+except ImportError:
+    from langchain.tools.python.tool import PythonAstREPLTool
+
+# Optional: LangSmith Tracing
+try:
+    from langchain_community.tracing import configure_langsmith
+except ImportError:
+    configure_langsmith = None
 
 # ---------------------------------------------------------------------
 # 0) Optionale LangSmith-Tracing  (setze ENV: LANGCHAIN_API_KEY)