Hello.
In mnya problem with the solution of the problem:
Locally, I have worked faithfully.
But in your test system at the 3 best samples gives no true result.
From: https://checkio.org/mission/find-friends/
HTTP_USER_AGENT:
Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.102 Safari/537.36
Created at: 2016/05/19 14:10; Updated at: 2016/05/23 11:26