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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 rollback_group(self, group_id, version, force=False):
 """Roll a group back to a previous version. :param str group_id: group ID :param str version: group version :param bool force: apply even if a deployment is in progress :returns: a dict containing the deployment id and version :rtype: dict """

        params = {'force': force}
        response = self._do_request(
            'PUT',
            '/v2/groups/{group_id}/versions/{version}'.format(
                group_id=group_id, version=version),
            params=params)
        return response.json()