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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_group_members(self, group_name):
 """Get group members via provisioning API. If you get back an error 999, then the provisioning API is not enabled. :param group_name: name of group to list members :returns: list of group members :raises: HTTPResponseError in case an HTTP error status was returned """

        res = self._make_ocs_request(
            'GET',
            self.OCS_SERVICE_CLOUD,
            'groups/' + group_name
        )

        if res.status_code == 200:
            tree = ET.fromstring(res.content)
            self._check_ocs_status(tree, [100])
            return [group.text for group in tree.find('data/users')]

        raise HTTPResponseError(res)