Lock Host Objects in WATO

I found the following:

https://lists.mathias-kettner.de/pipermail/checkmk-commits/2018-November/024212.html

But its not working in 1.6. Tried the following:

# Created by WATO
# encoding: utf-8
_lock = False
all_hosts += ['xxx']

host_tags.update({'test': {'piggyback': 'auto-piggyback', 'networking': 'lan', 'agent': 'cmk-agent', 'criticality': 'offline', 'snmp_ds': 'no-snmp', 'ip-v4': 'ip-v4', 'ping': 'ping', 'site': 'xyz', 'tcp': 'tcp', 'address_family': 'ip-v4-only'}})

host_labels.update({})

# Host attributes (needed for WATO)
host_attributes.update(
{'test': {
    'meta_data': {
        'created_at': 1649158402.524705,
        'created_by': u'myself'
        },
    'locked': {
        "locked_by": ("site_id", "dcd", "connection-id"),
        "attributes": [
            "alias",
            "ipaddress",
            "ipv6address",
            ],
        }
    }
})