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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def tween(self, t):
 """ t is number between 0 and 1 to indicate how far the tween has progressed """

        if t is None:
            return None

        if self.method in self.method_to_tween:
            return self.method_to_tween[self.method](t)
        elif self.method in self.method_1param:
            return self.method_1param[self.method](t, self.param1)
        elif self.method in self.method_2param:
            return self.method_2param[self.method](t, self.param1, self.param2)
        else:
            raise Exception("Unsupported tween method {0}".format(self.method))