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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 release(self, id):
 """Get a single release. :param int id: (required), id of release :returns: :class:`Release <github3.repos.release.Release>` """

        json = None
        if int(id) > 0:
            url = self._build_url('releases', str(id), base_url=self._api)
            json = self._json(self._get(url), 200)
        return Release(json, self) if json else None