A deep NLA to pass into a link.add

[nowayelse]

The doc says:

All other keywords will be translated to NLA names, e.g. mtu -> IFLA_MTU, af_spec -> IFLA_AF_SPEC etc. You can provide a complete NLA structure or let filters do it for you.
I gonna change a ipv6 autoconf and other ipv6 properties during ipr.link('add') or 'set', passing a keyword as short form:

inet6_conf={'disable_ipv6': 1, 'autoconf': 0},

or as NLA structure:

IFLA_AF_SPEC={'attrs': [['AF_INET6', {'attrs':[['IFLA_INET6_CONF', {'disable_ipv6': 1, 'autoconf':0}]]}]]},

Both of them do not work.
How to prepare a correct inet6_conf keyword?

[nowayelse]

More details.
I suppose my complete NLA from second quote is correct because it is equal to nested NLA got via ns.get_links(index)[0].get(('af_spec',)), with additionally deleted unneed NLAs from inside and then made a .dump().
So,

ns.link(
  'add',
  ifname=name,
  link=parent_index,
  IFLA_AF_SPEC={'attrs': [['AF_INET6', {'attrs': [['IFLA_INET6_CONF', {'accept_ra': 1, 'autoconf': 0}]]}]]},
  kind='vlan',
  vlan_id=vlan,
  net_ns_fd='new_ns')

raises this:

File "/home/nwe/.local/lib/python3.10/site-packages/pyroute2/iproute/linux.py", line 1672, in link
ret = self.nlm_request(msg, msg_type=msg_type, msg_flags=msg_flags)
File "/home/nwe/.local/lib/python3.10/site-packages/pyroute2/netlink/nlsocket.py", line 870, in nlm_request
return tuple(self._genlm_request(*argv, **kwarg))
File "/home/nwe/.local/lib/python3.10/site-packages/pyroute2/netlink/nlsocket.py", line 1214, in nlm_request
for msg in self.get(
File "/home/nwe/.local/lib/python3.10/site-packages/pyroute2/netlink/nlsocket.py", line 873, in get
return tuple(self._genlm_get(*argv, **kwarg))
File "/home/nwe/.local/lib/python3.10/site-packages/pyroute2/netlink/nlsocket.py", line 550, in get
raise msg['header']['error']
pyroute2.netlink.exceptions.NetlinkError: (22, 'Invalid argument')

[nowayelse]

I have found a w/a. Or a proper solution.
IFLA_AF_SPEC={'attrs': [['AF_INET6', {'attrs': [['IFLA_INET6_ADDR_GEN_MODE', 1]]}]]}