Update agent.py

agent.py

@@ -4,7 +4,7 @@ from langchain_core.tools import tool
 from langchain_openai import ChatOpenAI
 from langgraph.graph import END, StateGraph
 from langgraph.prebuilt import ToolNode
-from langchain.tools import DuckDuckGoSearchResults
+from langchain_community.tools import DuckDuckGoSearchResults
 from langchain_community.utilities import WikipediaAPIWrapper
 from langchain.agents import create_tool_calling_agent
 from langchain.agents import AgentExecutor
@@ -12,7 +12,6 @@ from langchain_core.prompts import ChatPromptTemplate, MessagesPlaceholder
 import operator
 import json
 
-
 # Define the agent state
 class AgentState(TypedDict):
     messages: Annotated[Sequence[BaseMessage], operator.add]
@@ -32,9 +31,9 @@ def web_search(query: str, num_results: int = 3) -> list:
 @tool
 def calculate(expression: str) -> str:
     """Evaluate mathematical expressions."""
-    from langchain.chains import LLMMathChain
-    llm = ChatOpenAI(model="gpt-3.5-turbo", temperature=0)
-    return LLMMathChain(llm=llm).run(expression)
+    from langchain_experimental.tools import PythonREPLTool
+    python_repl = PythonREPLTool()
+    return python_repl.run(f"print({expression})")
 
 class AdvancedAIAgent:
     def __init__(self, model_name="gpt-4-turbo"):
@@ -65,7 +64,7 @@ class AdvancedAIAgent:
         
         # Define nodes
         workflow.add_node("agent", self._call_agent)
-        workflow.add_node("tools", ToolNode(self.tools))  # Using ToolNode instead of ToolExecutor
+        workflow.add_node("tools", ToolNode(self.tools))
         
         # Define edges
         workflow.set_entry_point("agent")