Update app.py

app.py

@@ -9,7 +9,7 @@ from Gradio_UI import GradioUI
 
 # Below is an example of a tool that does nothing. Amaze us with your creativity !
 @tool
-def convert_currency(amount: float, from_currency: float, to_currency: float) -> float:
+def convert_currency(amount: float, from_currency: str, to_currency: str) -> str:
     """
     Converts an amount from one currency to another using a static exchange rate list.