code: func NewProxyExecMode(raw string) (ProxyExecMode, error) {
  	switch raw {
  	case "":
  		return ProxyExecModeUnspecified, nil
  	case "daemon":
  		return ProxyExecModeDaemon, nil
  	case "script":
  		return ProxyExecModeScript, nil
  	default:
  		return 0, fmt.Errorf("invalid exec mode: %s", raw)
  	}
  }
docs: // NewProxyExecMode returns the proper ProxyExecMode for the given string value.