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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 slug(self):
 """ A concise slug for this feature. Unlike the internal representation, which is 0-based half-open, the slug is a 1-based closed interval (a la GFF3). """

        return '{:s}@{:s}[{:d}, {:d}]'.format(self.type, self.seqid,
                                              self.start + 1, self.end)