def test_filling_set_correctly(self):
     n = SausageLinkNode("beef", None, None)
     self.assertEqual(n.contains_a_specific_filling("beef"), True)
 def test_set_prev_node(self):
     n = SausageLinkNode("emu", None, None)
     o = SausageLinkNode("pork", None, None)
     n.set_prev_node(o)
     self.assertEqual(n.prev_node, o)