look at the code if you want to know what i did

data/protocol_version.go

@@ -12,7 +12,7 @@ package data
 type VersionInfo struct {
 	MinecraftVersion string
 	Version          int32
-	DataVersion      int
+	DataVersion      int32
 	UsesNetty        bool
 	MajorVersion     string
 	ReleaseType      string
@@ -42,6 +42,16 @@ func LookUpVersionByProtocolVersion(version int32) (ret VersionInfo, err error)
 	return
 }
 
+func LookUpVersionByDataVersion(version int32) (ret VersionInfo, err error) {
+	for _, v := range ProtocolVersions {
+		if v.DataVersion == version {
+			ret = v
+		}
+	}
+	err = UnknownMinecraftVersionError
+	return
+}
+
 func init() {
 	must(LoadJson("minecraft-data/data/pc/common/protocolVersions.json", &ProtocolVersions))
 }