'Find a E-Series snapshot by its Cinder identifier
An E-Series snapshot image does not have a configuration name/label,
so we define a snapshot volume underneath of it that will help us to
identify it. We retrieve the snapshot volume with the matching name,
and then we find its underlying snapshot.
:param snapshot_id: Cinder snapshot identifer
:return: An E-Series snapshot image'

def _get_snapshot(self, snapshot):

    try:
        return self._client.list_snapshot_image(snapshot.get('provider_id'))
    except (eseries_exc.WebServiceException, exception.NetAppDriverException):
        try:
            LOG.debug('Unable    to    locate    snapshot    by    its    id,    falling    back    to    legacy    behavior.')
            return self._get_snapshot_legacy(snapshot)
        except exception.NetAppDriverException:
            raise exception.NotFound((_('Snapshot    with    id    of    %s    could    not    be    found.') % snapshot['id']))
