input: 
  def get_greatest_2(items: List[int]) -> Tuple[int, int]:
      """ Return the greatest two numbers from a given list of integers.
      If the list has fewer than two elements, it should return (float('-inf'), float('-inf')).
      >>> get_greatest_2([1, 5, 3, 7, 4, 7, 8, 9, 2, 10, 6, 8])
      (10, 9)
      >>> get_greatest_2([1, 2])
      (2, 1)
      >>> get_greatest_2([5])
      (5, float('-inf'))
      """
      if len(items) < 2:
          return (float('-inf'), float('-inf'))
      max1 = max2 = float('-inf')
      for item in items:
          if item > max1:
              max1, max2 = item, max1
          elif item > max2:
              max2 = item
      return max1, max2
  
output:     if len(items) < 2:
          return (float('-inf'), float('-inf'))
      max1 = max2 = float('-inf')
      for item in items:
          if item > max1:
              max1, max2 = item, max1
          elif item > max2:
              max2 = item
      return max1, max2