input: def double_add(num1: int, num2: int) -> int: 
      """Adds two integers and then doubles the result.
      >>> double_add(2, 3)
      10
      >>> double_add(-1, 1)
      0
      >>> double_add(0, 0)
      0
      """
      return (num1 + num2) * 2
output:     return (num1 + num2) * 2