diff --git a/src/wp-includes/blocks/template-part.php b/src/wp-includes/blocks/template-part.php
index 3837a0a17d..bef49341d7 100644
--- a/src/wp-includes/blocks/template-part.php
+++ b/src/wp-includes/blocks/template-part.php
@@ -22,7 +22,7 @@ function render_block_core_template_part( $attributes ) {
 	if (
 		isset( $attributes['slug'] ) &&
 		isset( $attributes['theme'] ) &&
-		get_stylesheet() === $attributes['theme']
+		wp_get_theme()->get_stylesheet() === $attributes['theme']
 	) {
 		$template_part_id    = $attributes['theme'] . '//' . $attributes['slug'];
 		$template_part_query = new WP_Query(