Geo Open is an IP address geolocation per country in MMDB format. The database can be used as a replacement for software using the MMDB format.

Information about MMDB format: https://maxmind.github.io/MaxMind-DB/
Open source server using Geo Open: https://github.com/adulau/mmdb-server
Open source library to read MMDB file: https://github.com/maxmind/MaxMind-DB-Reader-python
Historical dataset: https://cra.circl.lu/opendata/geo-open/

The database is automatically generated from public BGP AS announces matching the country code. The precision is at country level.