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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 add_repo(self, repo):
 """Add ``repo`` to this team. :param str repo: (required), form: 'user/repo' :returns: bool """

        url = self._build_url('repos', repo, base_url=self._api)
        return self._boolean(self._put(url), 204, 404)