from oslo_config import cfg
import oslo_messaging as m

cfg.CONF.set_override('lock_path', '/tmp', group='oslo_concurrency')

transport = m.get_rpc_transport(cfg.CONF, url='unix:/tmp')
target = m.Target(topic='test')

client = m.get_rpc_client(
    transport,
    target,
)

r = client.prepare(timeout=10).call(
    None,
    'coucou',
    arg='boy'
)
print(f'{r=}')