How to use the @polkadot/ui-keyring.addExternal function in @polkadot/ui-keyring

const _onSave = (): void => {
    if (!scanned || !isNameValid) {
      return;
    }

    const { address, genesisHash } = scanned;

    keyring.addExternal(address, { genesisHash, name: name.trim() });
    InputAddress.setLastValue('account', address);

    onStatusChange({
      account: address,
      action: 'create',
      message: t('created account'),
      status: 'success'
    });
    onClose();
  };

private accountsCreateExternal ({ address, genesisHash, name }: RequestAccountCreateExternal): boolean {
    keyring.addExternal(address, { name, genesisHash });

    return true;
  }