Added more information to doc string

app.py

@@ -14,7 +14,7 @@ def my_calculator(arg1:int, arg2:int, op:str)-> int: #it's import to specify the
     Args:
         arg1: the first argument
         arg2: the second argument
-        op: the operation
+        op: the operation, e.g. multiplication, division, addition, or subtraction.
     """
     match op:
         case "*" | "multiplication":