limit connections

[edX project]

good day everyone, im trying to limit user connections to my openedx instance, im trying to do this with nginx`s geoip module. But everytime im getting an error. I've added map $geoip_country_code $good_country {

        default yes;

        CZ no;

        AZ no;

        UA no; 

        }

to nginx.conf file, and 

set $allowedips 0;

  if ($good_country = no) {

            set $allowedips 1;

  }

  if ($allowedips = 1) {

        return 404;

  }

to my sites-available/lms file. but its not working...

Is it real to make it?