Update app.py

app.py

@@ -25,7 +25,7 @@ def add_num(num1: float, num2: float)-> float:
         num1: first number
         num2: second number
     """
-    return a + b
+    return num1 + num2
 
 @tool
 def get_current_time_in_timezone(timezone: str) -> str: