code: def image_height(image):
      
      image_size_cache = _get_cache('image_size_cache')
      if not Image:
          raise SassMissingDependency('PIL', 'image manipulation')
      filepath = String.unquoted(image).value
      path = None
      try:
          height = image_size_cache[filepath][1]
      except KeyError:
          height = 0
          IMAGES_ROOT = _images_root()
          if callable(IMAGES_ROOT):
              try:
                  _file, _storage = list(IMAGES_ROOT(filepath))[0]
              except IndexError:
                  pass
              else:
                  path = _storage.open(_file)
          else:
              _path = os.path.join(IMAGES_ROOT, filepath.strip(os.sep))
              if os.path.exists(_path):
                  path = open(_path, 'rb')
          if path:
              image = Image.open(path)
              size = image.size
              height = size[1]
              image_size_cache[filepath] = size
      return Number(height, 'px')
docs: Returns the height of the image found at the path supplied by `image`
      relative to your project's images directory.