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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_to_branch(self, release_id):
 """ Shortcut to translate a release identifier to a branch name. :param release_id: A :attr:`Release.identifier` value (a string). :returns: A branch name (a string). :raises: :exc:`~exceptions.TypeError` when :attr:`release_scheme` isn't 'branches'. """

        self.ensure_release_scheme('branches')
        return self.releases[release_id].revision.branch