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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_groups(self):
 """Get groups via provisioning API. If you get back an error 999, then the provisioning API is not enabled. :returns: list of groups :raises: HTTPResponseError in case an HTTP error status was returned """

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

        if res.status_code == 200:
            tree = ET.fromstring(res.content)
            groups = [x.text for x in tree.findall('data/groups/element')]

            return groups

        raise HTTPResponseError(res)