def strategy(self, opponent):
        if len(self.history) < 2:
            return "C"
        if opponent.history not in D:
            return D
        if opponent.history[-1] == D and self.history[-2] == D:
            return "C"
        return opponent.history[-1]
dataset/ETHPy150Open Axelrod-Python/Axelrod/axelrod/strategies/titfortat.py/SneakyTitForTat.strategy/swapped operands of `not in`