when i editer amp plugin error website

Parse error: syntax error, unexpected ‘@’, expecting ‘)’ in /home/con9464a/public_html/wp-content/plugins/amp/includes/class-amp-post-template.php on line 150

i setup follow :
http://searchengineland.com/get-started-accelerated-mobile-pages-amp-240688

https://ww.wp.xz.cn/plugins/amp/