@classmethod
def _extract_change(cls, build):
    """Extract the most recent change-set items from the build.

        Arguments:
          build (:py:class:`dict`): The JSON data from the response.

        Returns:
          :py:class:`tuple`: The author and message.

        """
    changes = build.get('changeSets')
    if not changes:
        return None, None
    items = changes[-1].get('items')
    if not items:
        return None, None
    item = items[0]
    return item.get('author', {}).get('fullName'), item.get('comment')
