includes/graphs/countries_pie.php

<?php

echo renderPieGraph(
    'countries_daily',
    'country',
    'views',
    t('section.countries'),
    $rangeSql,
    $rangeParams,
    $periodTitle,
    static fn(string $country): string => countryName($country),
    static fn(string $country): string => countryFlagUrl($country)
);