This tool is looking up country-code from MaxMind GeoIP2/GeoLite2 databases.
# echo -e "aaaa bbbb 183.79.71.173 ccc\nxxxx yyyy 173.194.126.134 zzz\n" | cclogconv --data /usr/share/GeoIP/GeoLite2-Country.mmdb
aaaa bbb JP 183.79.71.173 ccc
xxx yyyy US 173.194.126.134 zzz
# echo -e "aaaa bbbb 183.79.71.173 ccc\nxxxx yyyy 173.194.126.134 zzz\n" | cclogconv --data /usr/share/GeoIP/GeoLite2-Country.mmdb --cc=US
xxx yyyy US 173.194.126.134 zzz