Update app.py

app.py

@@ -35,7 +35,7 @@ def get_current_time_in_timezone(timezone: str) -> str:
 
 
 @tool
-def calculator(parameter_1: float, parameter_2: float) -> float | int:
+def calculator(parameter_1: float, parameter_2: float) -> str:
     """A tool with which you can add two arbitary float values.
     Args:
         parameter_1: a float value that represnets the first value.