Code review comment for lp:~mpontillo/maas/update-host-maps-cleanup-bug-1440102

This version didn't pass CI. I think I missed a spot where I need to do MAC(...) instead of assuming it's the proper type. (and not, say, unicode). Line 716 in the current diff:

ip_mapping = [(static_ip.ip, self.mac_address.get_raw())]