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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 discard(self, min_freq, unknown_token):
 """Discards tokens with frequency below min_frequency and represents them as `unknown_token`. Parameters min_freq: int Tokens whose frequency is under min_freq is counted as `unknown_token` in the Counter returned. unknown_token: str The representation for any unknown token. Returns ------- The Counter instance. Examples -------- Counter({'a': 10, '<unk>': 2}) """

        freq = 0
        ret = Counter({})
        for token, count in self.items():
            if count < min_freq:
                freq += count
            else:
                ret[token] = count
        ret[unknown_token] = ret.get(unknown_token, 0) + freq
        return ret