def services(namespace='default', **kwargs):
    '''
    Return a list of kubernetes services defined in the namespace

    CLI Examples::

        salt '*' kubernetes.services
        salt '*' kubernetes.services namespace=default
    '''
    cfg = _setup_conn(**kwargs)
    try:
        api_instance = kubernetes.client.CoreV1Api()
        api_response = api_instance.list_namespaced_service(namespace)

        return [srv['metadata']['name'] for srv in api_response.to_dict().get('items')]
    except (ApiException, HTTPError) as exc:
        if isinstance(exc, ApiException) and exc.status == 404:
            return None
        else:
            log.exception(
                'Exception when calling '
                'CoreV1Api->list_namespaced_service'
            )
            raise CommandExecutionError(exc)
    finally:
        _cleanup(**cfg)