if all(k in machine_spec for k in ['host', 'user']):
# Enlist an existing machine as a Juju unit
machine = await model.add_machine(spec='ssh:{}@{}:{}'.format(
if all(k in machine_spec for k in ['host', 'user']):
# Enlist an existing machine as a Juju unit
machine = await model.add_machine(spec='ssh:{}@{}:{}'.format(