Update app.py

app.py

@@ -15,7 +15,8 @@ def search_tool(arg1: str)-> str: #it's import to specify the return type
     Args:
         arg1: the first argument
     """
-    response = DuckDuckGoSearchTool(arg1=arg1)
+    search_tool = DuckDuckGoSearchTool()
+    response = search_tool(arg1=arg1)
     return response
 
 @tool