Can't execute json_decode function?

Question

PHP

Hello!
There was a problem, I do not understand what it is!
I get json remotely using file_get_content, I try to process it, it doesn’t work, NULL is given if I output a string and everything is ok.
Tried to check for errors with json_last_error(), got a Syntax error. I took the json itself, copied it into the validator, everything is ok.
How can the problem be solved?

$city = 'Красноярск';

$url = "http://www.pony-ex.ru/autocomplete/city?term=".urlencode($city);

$content = file_get_contents($url);

 print_r(json_decode($content, true));

Answer 1

print_r(json_decode(substr($content, 3), true));
y worked for me.
problem/solution

Answer 2

Before print_r paste
Is the result visible?