wp_get_default_update_php_url example

function wp_get_update_php_url() {
    $default_url = wp_get_default_update_php_url();

    $update_url = $default_url;
    if ( false !== getenv( 'WP_UPDATE_PHP_URL' ) ) {
        $update_url = getenv( 'WP_UPDATE_PHP_URL' );
    }

    /** * Filters the URL to learn more about updating the PHP version the site is running on. * * Providing an empty string is not allowed and will result in the default URL being used. Furthermore * the page the URL links to should preferably be localized in the site language. * * @since 5.1.0 * * @param string $update_url URL to learn more about updating PHP. */