code: def list_to_serialized(ref, the_list):
      
      result = []
      for elt in the_list:
          if not getattr(elt, 'serialize', None):
              continue
          result.append(elt.serialize())
      return result
docs: Serialize the list of elements
  
      Used for the retention store
  
      :param ref: Not used
      :type ref:
      :param the_list: dictionary to convert
      :type the_list: dict
      :return: dict of serialized
      :rtype: dict