input: def extract_positive_numbers(numbers: list):
      """Retrieve only the positive values from the given list.
      >>> extract_positive_numbers([-1, 2, -4, 5, 6])
      [2, 5, 6]
      >>> extract_positive_numbers([5, 3, -5, 2, -3, 3, 9, 0, 123, 1, -10])
      [5, 3, 2, 3, 9, 123, 1]
      """
output:     return [num for num in numbers if num > 0]