in src/geoip.rs [112:121]
fn test_geoip_works() -> Result<(), Box<dyn std::error::Error>> {
let geoip = super::GeoIp::builder()
.path("./GeoLite2-Country.mmdb")
.build()?;
let ip = "7.7.7.7".parse()?;
let rv = geoip.locate(ip).unwrap().unwrap();
assert_eq!(rv.country.unwrap().iso_code.unwrap(), "US");
Ok(())
}