Unity: detach all luns from host

[Murray-LIANG]

Currently, the user needs to do as follow to detach all LUNs from a host:

u = storops.UnitySystem(……
host = u.get_host(name='host-abc')
for lun in host.host_luns.lun:
    host.detach(lun)

All the attach/detach operation is done on the lun object including host.detach which calls lun.detach. Need to find out if there is any REST api for detaching all luns on host object in the engineering mode.