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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 publish_api(self, ret, stage_variables):
        '''
        this method tie the given stage_name to a deployment matching the given swagger_file
        '''
        stage_desc = dict()
        stage_desc['current_deployment_label'] = self.deployment_label
        stage_desc_json = _dict_to_json_pretty(stage_desc)

        if self._deploymentId:
            # just do a reassociate of stage_name to an already existing deployment
            res = self._set_current_deployment(stage_desc_json, stage_variables)
            if not res.get('set'):
                ret['abort'] = True
                ret['result'] = False
                ret['comment'] = res.get('error')
            else:
                ret = _log_changes(ret,
                                   'publish_api (reassociate deployment, set stage_variables)',
                                   res.get('response'))
        else:
            # no deployment existed for the given swagger_file for this Swagger object
            res = __salt__['boto_apigateway.create_api_deployment'](restApiId=self.restApiId,
                                                                    stageName=self._stage_name,
                                                                    stageDescription=stage_desc_json,
                                                                    description=self.deployment_label_json,
                                                                    variables=stage_variables,
                                                                    **self._common_aws_args)
            if not res.get('created'):
                ret['abort'] = True
                ret['result'] = False
                ret['comment'] = res.get('error')
            else:
                ret = _log_changes(ret, 'publish_api (new deployment)', res.get('deployment'))
        return ret