WordPress: Add the Hueman theme's sharing bar to pages. (Fix for those who don't have a recommended child theme)

hueman-theme-sharrre-sharing-bar-on-pages.php

<?php
/**
 * Plugin Name:       Hueman Theme - Sharrre Sharing Bar On Pages
 * Description:       Add the Hueman theme's sharing-bar to pages. (Fix for those who don't have a recommended child theme)
 * Plugin URI:        https://gist.github.com/birgire/be3dc8174e227233fa70
 * Author:            Birgir Erlendsson (birgire)
 * Author URI:        https://github.com/birgire
 * Version:           0.0.1
 * Licence:           MIT
 */

/**
 * Append the Sharrre sharing-bar to the page content
 */
add_filter( 'the_content', function( $content ) 
{
	if (      
		   ! is_admin() 
		&& in_the_loop() 
	        && is_page() 
 	        && function_exists( 'ot_get_option' ) 
		&& ot_get_option('sharrre') != 'off' 
	) { 
		ob_start();
		get_template_part('inc/sharrre'); 
		$content .= ob_get_clean();
		$content .= "<script>jQuery( '.entry.themeform').addClass( 'share' );</script>;";
	} 	
	return $content;
});