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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 astuple(self, encoding=None):
 """ Return a tuple suitable for import into a database. Attributes field and extra field jsonified into strings. The order of fields is such that they can be supplied as arguments for the query defined in :attr:`gffutils.constants._INSERT`. If `encoding` is not None, then convert string fields to unicode using the provided encoding. Returns ------- Tuple """

        if not encoding:
            return (
                self.id, self.seqid, self.source, self.featuretype, self.start,
                self.end, self.score, self.strand, self.frame,
                helpers._jsonify(self.attributes),
                helpers._jsonify(self.extra), self.calc_bin()
            )
        return (
            self.id.decode(encoding), self.seqid.decode(encoding),
            self.source.decode(encoding), self.featuretype.decode(encoding),
            self.start, self.end, self.score.decode(encoding),
            self.strand.decode(encoding), self.frame.decode(encoding),
            helpers._jsonify(self.attributes).decode(encoding),
            helpers._jsonify(self.extra).decode(encoding), self.calc_bin()
        )