show a 404 page when trying to access a profile page for members with "Hide from Directory?" checked and/or don't have a specific level

my_pmpromd_profile_preheader.php

//show a 404 page when trying to access a profile page for members with "Hide from Directory?" checked and/or don't have a specific level
function my_pmpromd_profile_preheader()
{
	// -------- Edit this line to determine which levels get profile pages ---------- //
	$directory_levels = array(1, 2, 3);

	global $post, $pmpro_pages, $current_user, $wp_query;
	if(!empty($post->ID) && $post->ID == $pmpro_pages['profile'])
	{
		//Get the profile user
		if(!empty($_REQUEST['pu']) && is_numeric($_REQUEST['pu']))
			$pu = get_user_by('id', $_REQUEST['pu']);
		elseif(!empty($_REQUEST['pu']))
			$pu = get_user_by('slug', $_REQUEST['pu']);
		elseif(!empty($current_user->ID))
			$pu = $current_user;
		else
			$pu = false;
		//Get the level for the profile user
		$level = pmpro_getMembershipLevelForUser($pu->ID);

		//If the profile user has "Hide from Directory?" checked or doesn't have an approved level, show a 404 page
		if(!empty($pu->pmpromd_hide_directory) || !isset($level->ID) || !in_array( $level->ID, $directory_levels ) )
		{
			$wp_query->set_404();
			status_header( 404 );
			get_template_part( 404 );
			exit;
		}
	}
}
add_action("wp", "my_pmpromd_profile_preheader", 2);