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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 enable_app(self, appname):
 """Enable an app through provisioning_api :param appname: Name of app to be enabled :returns: True if the operation succeeded, False otherwise :raises: HTTPResponseError in case an HTTP error status was returned """

        res = self._make_ocs_request('POST', self.OCS_SERVICE_CLOUD,
                                     'apps/' + appname)
        if res.status_code == 200:
            return True

        raise HTTPResponseError(res)