code: def _is_out_of_order(segmentation):
      
      last_stroke = -1
      for symbol in segmentation:
          for stroke in symbol:
              if last_stroke > stroke:
                  return True
              last_stroke = stroke
      return False
docs: Check if a given segmentation is out of order.
  
      Examples
      --------
      >>> _is_out_of_order([[0, 1, 2, 3]])
      False
      >>> _is_out_of_order([[0, 1], [2, 3]])
      False
      >>> _is_out_of_order([[0, 1, 3], [2]])
      True