def test_node_set_maintenance(self):
        node_show = self.show_node(self.node['uuid'])

        self.assertEqual('False', node_show['maintenance'])

        self.set_node_maintenance(
            self.node['uuid'],
            "true --reason 'Testing node-set power state command'")
        node_show = self.show_node(self.node['uuid'])

        self.assertEqual('True', node_show['maintenance'])
        self.assertEqual('Testing node-set power state command',
                         node_show['maintenance_reason'])
Test steps:
dataset/ETHPy150Open openstack/python-ironicclient/ironicclient/tests/functional/test_node.py/NodeSanityTestIronicClient.test_node_set_maintenance