Show the "Favorite" button ONLY to members of Level ID 1 when using the Favorites Plugin for WordPress Raw

my_pmpro_level_1_only_favorites.php

<?php
/*
  This recipe restricts display of the "Favorite" button for 
  the Favorites Plugin by Kyle Phillips (https://wordpress.org/plugins/favorites/).
  
  Be sure to turn off the automatic display of the button under Settings > Favorites > Display.
  The button will be shown to members of Level ID 1 only.
*/
function my_pmpro_level_1_only_favorites( $content ) {
	//Don't show the favorites button on PMPro pages 
	$excluded_pages = array(pmpro_getOption('billing_page_id'), pmpro_getOption('account_page_id'), pmpro_getOption('levels_page_id'), pmpro_getOption('checkout_page_id'), pmpro_getOption('confirmation_page_id'));
	
	//Show the favorites button for members of level 1
	if( function_exists( 'pmpro_hasMembershipLevel' ) && 
		pmpro_hasMembershipLevel( '1' ) && 			//update this line with your level ID
		//'post' === get_post_type(  ) &&			//add this line to restrict to 'posts' only
		!is_page( $excluded_pages ) ) {
			if( function_exists( 'get_favorites_button) {
				$content .= get_favorites_button();
			}
	}
	return $content;
}
add_filter( 'the_content', 'my_pmpro_level_1_only_favorites' );

Line 18 needs a fix as per my gist https://gist.github.com/tajdara/6314a9fd903726876122c260a0a0413f

This recipe is included in the blog post on "Allow Members to Favorite Posts using the Favorites Plugin for WordPress" at Paid Memberships Pro here: https://www.paidmembershipspro.com/allow-members-favorite-posts-using-favorites-plugin-wordpress/