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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 swapped(self):
 """ Swap query and subject. """

        args = [getattr(self, attr) for attr in BlastLine.__slots__[:12]]
        args[0:2] = [self.subject, self.query]
        args[6:10] = [self.sstart, self.sstop, self.qstart, self.qstop]
        if self.orientation == '-':
            args[8], args[9] = args[9], args[8]
        b = "\t".join(str(x) for x in args)
        return BlastLine(b)