如何在go中将具有不同日志级别的附加程序设置到同一golog.logger？

I'm using this package to handle my go project logs: https://github.com/ivpusic/golog; I don't know how can I set appender with different levels to one logger. Can anybody help me with this?

I want to have something like this:

package main

import (
    "github.com/ivpusic/golog"
    "github.com/ivpusic/golog/appenders"
)

func main() {
    logger := golog.Default

    fileAppender := appenders.File(golog.Conf{
        "path": "/path/to/file.log",
    })

    mongoAppender := appenders.Mongo(golog.Conf{
        "host":        "localhost:27017",
        "db":          "mongolog",
        "colllection": "carpooling_chat_log",
    })

    fileAppender.Level = golog.DEBUG
    mongoAppender.Level = golog.INFO

    logger.Enable(fileAppender)
    logger.Enable(mongoAppender)
}