correct load_tools defect

app.py

@@ -83,9 +83,9 @@ llm = chat
 #     description ='Useful for when you need to answer questions about math.'
 # )
 
-tools = [DB_Search(), duckduckgo_tool, python_tool]
+# tools = [DB_Search(), duckduckgo_tool, python_tool]
 
-tools = load_tools(["llm-math"], llm=llm)
+tools = load_tools(["DB_Search","duckduckgo_tool","python_tool","llm-math"], llm=llm)
 
 embeddings = OpenAIEmbeddings(deployment="model_embedding", chunk_size=15)