WordPress Version: 5.5
/**
* Registers a new sitemap provider.
*
* @since 5.5.0
*
* @param string $name Unique name for the sitemap provider.
* @param WP_Sitemaps_Provider $provider The `Sitemaps_Provider` instance implementing the sitemap.
* @return bool Whether the sitemap was added.
*/
function wp_register_sitemap_provider($name, WP_Sitemaps_Provider $provider)
{
$sitemaps = wp_sitemaps_get_server();
return $sitemaps->registry->add_provider($name, $provider);
}