'Return LUN for allocation specified in location string'

def _find_target_lun(self, location):

    resp = self._send_cmd('GET', location)
    status = resp['status']
    if (status != 200):
        LOG.error('Failed    to    get    allocation    information    (%d)!', status)
        RaiseXIODriverException()
    xml_tree = etree.fromstring(resp['content'])
    allocation = xml_tree.find('allocation')
    if (allocation is not None):
        luntag = allocation.find('lun')
        if (luntag is not None):
            return luntag.text
    LOG.error('Failed    to    get    LUN    information!')
    RaiseXIODriverException()
