'Require that groups have children groups or hosts, not both.'

def test_group_with_hosts_dont_have_children(self):

    inventory = get_inventory()
    for (key, values) in inventory.items():
        has_children = bool(inventory.get('children'))
        has_hosts = bool(inventory.get('hosts'))
        self.assertFalse((has_children and has_hosts))
