'Retrieve a single tag.
:param tag_id: ID of the tag to retrieve.
:type tag_id: ``str``
:rtype: ``list`` of :class:`.CloudSigmaTag` objects'

def ex_get_tag(self, tag_id):

    action = ('/tags/%s/' % tag_id)
    response = self.connection.request(action=action, method='GET').object
    tag = self._to_tag(data=response)
    return tag
