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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 f_comb(self, pos, sample):
 """return the value of the f_comb when epoch = pos Parameters pos: int the epoch number of the position you want to predict sample: list Returns ------- int The expected matrix at pos with all the active function's prediction """

        ret = 0
        for i in range(self.effective_model_num):
            model = self.effective_model[i]
            y = self.predict_y(model, pos)
            ret += sample[i] * y
        return ret