docs: def detach(self, connection_info):
          """Detach a volume from a guest
          """
          fcp = connection_info['zvm_fcp']
          fcp = fcp.lower()
          target_wwpn = connection_info['target_wwpn']
          target_lun = connection_info['target_lun']
          assigner_id = connection_info['assigner_id']
          assigner_id = assigner_id.upper()
          multipath = connection_info['multipath']
          os_version = connection_info['os_version']
          mount_point = connection_info['mount_point']
  
          if not zvmutils.check_userid_exist(assigner_id):
              LOG.error("Guest '%s' does not exist" % assigner_id)
              raise exception.SDKObjectNotExistError(
                      obj_desc=("Guest '%s'" % assigner_id), modID='volume')
          else:
              self._detach(fcp, assigner_id, target_wwpn, target_lun,
                           multipath, os_version, mount_point)