code: def list_notifications(self, client=None):
          
          client = self._require_client(client)
          path = self.path + "/notificationConfigs"
          iterator = page_iterator.HTTPIterator(
              client=client,
              api_request=client._connection.api_request,
              path=path,
              item_to_value=_item_to_notification,
          )
          iterator.bucket = self
          return iterator
docs: List Pub / Sub notifications for this bucket.
  
          See:
          https://cloud.google.com/storage/docs/json_api/v1/notifications/list
  
          If :attr:`user_project` is set, bills the API request to that project.
  
          :type client: :class:`~google.cloud.storage.client.Client` or
                        ``NoneType``
          :param client: Optional. The client to use.  If not passed, falls back
                         to the ``client`` stored on the current bucket.
  
          :rtype: list of :class:`.BucketNotification`
          :returns: notification instances