def test_strategy(self):

        self.first_play_test(C)

        # Forgives three defections
        self.responses_test([C], [D], [C], tournament_length=200)
        self.responses_test([C, C], [D, D], [C], tournament_length=200)
        self.responses_test([C, C, C], [D, D, D], [C], tournament_length=200)
        self.responses_test([C, C, C, C], [D, D, D, D], [D],
                            tournament_length=200)

        # If opponent did not defect in the first six rounds, cooperate until
        # round 180
        self.responses_test([C] * 6, [C] * 6, [C] * 174, tournament_length=200)
        self.responses_test([C] * 12, [C] * 6 + [D] + [C] * 5, [C] * 160,
                            tournament_length=200)

        # Defects on rounds 199, and 200 no matter what
        self.responses_test([C] * 197 , [C] * 197, [C, D, D],
                            tournament_length=200)
Forgives the first 3 defections but on the fourth
dataset/ETHPy150Open Axelrod-Python/Axelrod/axelrod/tests/unit/test_backstabber.py/TestDoubleCrosser.test_strategy