code: def delete_persistent_attributes(self):
          # type: () -> None
          
          if not self._persistence_adapter:
              raise AttributesManagerException(
                  "Cannot delete PersistentAttributes without "
                  "persistence adapter!")
          if self._persistent_attributes_set:
              self._persistence_adapter.delete_attributes(
                  request_envelope=self._request_envelope)
              self._persistence_attributes = {}
              self._persistent_attributes_set = False
docs: Deletes the persistent attributes from the persistence layer.
          :rtype: None
          :raises: :py:class: `ask_sdk_core.exceptions.AttributesManagerException`
              if trying to delete persistence attributes without persistence adapter