'Get the least used NSP for the current host.
Steps to determine which NSP to use.
* If only one iSCSI NSP, return it
* If there is already an active vlun to this host, return its NSP
* Return NSP with fewest active vluns'

def _get_least_used_nsp_for_host(self, common, hostname):

    iscsi_nsps = self._get_iscsi_nsps(common)
    if (len(iscsi_nsps) == 1):
        return iscsi_nsps[0]
    vluns = common.client.getVLUNs()
    for vlun in vluns['members']:
        if vlun['active']:
            if (vlun['hostname'] == hostname):
                temp_nsp = common.build_nsp(vlun['portPos'])
                if (temp_nsp in iscsi_nsps):
                    return temp_nsp
    least_used_nsp = self._get_least_used_nsp(common, vluns['members'], self._get_iscsi_nsps(common))
    return least_used_nsp
