docs: def get_item_abspath(self, identifier):
          """Return absolute path at which item content can be accessed.
  
          :param identifier: item identifier
          :returns: absolute path from which the item content can be accessed
          """
          manifest = self.get_manifest()
          item = manifest["items"][identifier]
          item_abspath = os.path.join(self._data_abspath, item["relpath"])
          return item_abspath