'Get the lun ID for an exported volume.
If the lun is successfully assigned (exported) to a client, the
client info has the lun_id.
Note: The structure returned for iscsi is different from the
one returned for FC. Therefore this function is here instead of
common.
Arguments:
volume_name -- name of volume to query for lun ID
client_name -- name of client associated with the volume
Returns:
lun_id -- Returns True or False'

def _is_lun_id_ready(self, volume_name, client_name):

    lun_id = (-1)
    lun_id = self._get_lun_id(volume_name, client_name)
    if (lun_id is None):
        return False
    else:
        return True
