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/**
 * Filter collection parameters for the posts controller.
 * @param array         $query_params JSON Schema-formatted collection parameters
 * @param WP_Post_Type  $post_type Post type object.
 */
add_filter('rest_product_collection_params', function ($query_params, $post_type) {
    $query_params['per_page']['maximum'] = 1000;
    return $query_params;
}, 10, 2);