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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 mask_right(self, n_seq_bases, mask="S"):
 """ Return a new cigar with cigar string where the last `n_seq_bases` are soft-masked unless they are already hard-masked. """

        return Cigar(Cigar(self._reverse_cigar()).mask_left(n_seq_bases, mask)._reverse_cigar())