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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 get_user_subadmin_groups(self, user_name):
 """Get a list of subadmin groups associated to a user. :param user_name: name of user :returns: list of subadmin groups :raises: HTTPResponseError in case an HTTP error status was returned """


        res = self._make_ocs_request(
            'GET',
            self.OCS_SERVICE_CLOUD,
            'users/' + user_name + '/subadmins',
        )

        if res.status_code == 200:
            tree = ET.fromstring(res.content)
            self._check_ocs_status(tree, [100])

            groups = tree.find('data')

            return groups

        raise HTTPResponseError(res)