code: def get_cache_key(page, language):
      
      from cms.cache import _get_cache_key
      try:
          site_id = page.node.site_id
      except AttributeError:  # CMS_3_4
          site_id = page.site_id
      return _get_cache_key('page_meta', page, language, site_id)
docs: Create the cache key for the current page and language