Imports github.com/maxmind/mmdbwriter github.com/maxmind/mmdbwriter/mmdbtype github.com/sagernet/sing-box/common/geosite github.com/sagernet/sing-box/common/srs github.com/sagernet/sing-box/option golang.org/x/text/encoding/charmap Standard library imports bufio encoding/json errors flag fmt io log net net/http os path/filepath regexp strings time