def test_children_concrete_classes(self):
     """
     Test ConcreteArpDomain _get_children_concrete_classes returns something list-like
     """
     node_id = '103'
     node = Node(node_id)
     concreteArp = ConcreteArp(node)
     concreteArpDomain = ConcreteArpDomain(concreteArp)
     self.assertTrue(
         isinstance(
             concreteArpDomain._get_children_concrete_classes(),
             list))
     for child in concreteArpDomain._get_children_concrete_classes():
         self.assertFalse(isinstance(child, ConcreteArpEntry))