refactor: remove unused imports and clarify decorator usage in calculator function

app.py

@@ -1,5 +1,4 @@
 # Super minimal app.py for troubleshooting
-from json import tool
 import gradio as gr
 import sys
 
@@ -14,18 +13,18 @@ for name, module in sys.modules.items():
 def echo(text):
     return f"You said: {text}"
   
-@tool
+# @tool # This decorator's origin is unclear or its library is not imported.
+# If it's from a library like langchain, ensure it's installed and imported.
+# For a minimal example, it's safer to remove it if its definition isn't present.
 def calculator(a: int, b: int) -> int:
     """Multiply two integers."""
     return a * b
 
-print(calculator.to_string())
-
 # Create a simple Gradio interface
 demo = gr.Interface(
     fn=calculator,
-    inputs=gr.Textbox(placeholder="Enter two numbers you want to multiply..."),
-    outputs=gr.Textbox(),
+    inputs=[gr.Number(label="First Number (a)"), gr.Number(label="Second Number (b)")],
+    outputs=gr.Number(label="Result (a * b)"),
     title="Micro Learning Platform - Debug Version",
     description="This is a minimal version for troubleshooting"
 )