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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 generate(self):
 """ Generates a new token for this column based on its bit length. This method will not ensure uniqueness in the model itself, that should be checked against the model records in the database first. :return: <str> """

        try:
            model = self.schema().model()
        except AttributeError:
            return os.urandom(self.__bits).encode('hex')
        else:
            while True:
                token = os.urandom(self.__bits).encode('hex')
                if model.select(where=orb.Query(self) == token).count() == 0:
                    return token