old_contents: # This class handles sprite sheets
  # This was taken from www.scriptefun.com/transcript-2-using
  # sprite-sheets-and-drawing-the-background
  # I've added some code to fail if the file wasn't found..
  # Note: When calling images_at the rect is the format:
  # (x, y, x + offset, y + offset)
   
  import pygame
   
  class spritesheet(object):
      def __init__(self, filename):
          try:
              self.sheet = pygame.image.load(filename).convert()
          except pygame.error, message:
              print 'Unable to load spritesheet image:', filename
              raise SystemExit, message
      # Load a specific image from a specific rectangle
      def image_at(self, rectangle, colorkey = None):
          "Loads image from x,y,x+offset,y+offset"
          rect = pygame.Rect(rectangle)
          image = pygame.Surface(rect.size).convert()
          image.blit(self.sheet, (0, 0), rect)
          if colorkey is not None:
              if colorkey is -1:
                  colorkey = image.get_at((0,0))
              image.set_colorkey(colorkey, pygame.RLEACCEL)
          return image
      # Load a whole bunch of images and return them as a list
      def images_at(self, rects, colorkey = None):
          "Loads multiple images, supply a list of coordinates" 
          return [self.image_at(rect, colorkey) for rect in rects]
      # Load a whole strip of images
      def load_strip(self, rect, image_count, colorkey = None):
          "Loads a strip of images and returns them as a list"
          tups = [(rect[0]+rect[2]*x, rect[1], rect[2], rect[3])
                  for x in range(image_count)]
          return self.images_at(tups, colorkey)
  
new_contents: # This class handles sprite sheets
  # This was taken from www.scriptefun.com/transcript-2-using
  # sprite-sheets-and-drawing-the-background
  # I've added some code to fail if the file wasn't found..
  # Note: When calling images_at the rect is the format:
  # (x, y, x + offset, y + offset)
  # Adapted for Py3k by Andy Russell
   
  import pygame
   
  class SpriteSheet(object):
      def __init__(self, filename):
          try:
              self.sheet = pygame.image.load(filename).convert()
          except pygame.error as message:
              print('Unable to load spritesheet image:', filename)
              raise SystemExit(message)
      # Load a specific image from a specific rectangle
      def image_at(self, rectangle, colorkey = None):
          "Loads image from x,y,x+offset,y+offset"
          rect = pygame.Rect(rectangle)
          image = pygame.Surface(rect.size).convert()
          image.blit(self.sheet, (0, 0), rect)
          if colorkey is not None:
              if colorkey is -1:
                  colorkey = image.get_at((0,0))
              image.set_colorkey(colorkey, pygame.RLEACCEL)
          return image
      # Load a whole bunch of images and return them as a list
      def images_at(self, rects, colorkey = None):
          "Loads multiple images, supply a list of coordinates" 
          return [self.image_at(rect, colorkey) for rect in rects]
      # Load a whole strip of images
      def load_strip(self, rect, image_count, colorkey = None):
          "Loads a strip of images and returns them as a list"
          tups = [(rect[0]+rect[2]*x, rect[1], rect[2], rect[3])
                  for x in range(image_count)]
          return self.images_at(tups, colorkey)
  
subject: fix spritesheet for python3