code: def commit_comment(self, comment_id):
          
          url = self._build_url('comments', str(comment_id), base_url=self._api)
          json = self._json(self._get(url), 200)
          return RepoComment(json, self) if json else None
docs: Get a single commit comment.
  
          :param int comment_id: (required), id of the comment used by GitHub
          :returns: :class:`RepoComment <github3.repos.comment.RepoComment>` if
              successful, otherwise None