input: Write a function to generate a Python program that adds two given numbers then doubles the result. The function should take two parameters and return the result.
  
  def double_add(num1, num2):
      return (num1 + num2) * 2
  
  assert double_add(2, 3) == 10
  assert double_add(0, 5) == 10
  assert double_add(-1, -1) == -4
  assert double_add(10, 0) == 20
  assert double_add(-5, 5) == 0
output: def double_add(num1, num2):
      return (num1 + num2) * 2