You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: logcat.go
    path of file: ./repos/netbird/formatter
    
    the code of the file until where you have to start completion: package formatter

import (
	"fmt"
	"strings"

	"github.com/sirupsen/logrus"
)

// LogcatFormatter formats logs into text what is fit for logcat
type LogcatFormatter struct {
	levelDesc []string
}

// NewLogcatFormatter create new LogcatFormatter instance
func NewLogcatFormatter() *LogcatFormatter {
	return &LogcatFormatter{
		levelDesc: [
    
func (f *LogcatFormatter) Format(entry *logrus.Entry) ([]byte, error) {
	var fields string
	keys := make([]string, 0, len(entry.Data))
	for k, v := range entry.Data {
		if k == "source" {
			continue
		}
		keys = append(keys, fmt.Sprintf("%s: %v", k, v))
	}

	if len(keys) > 0 {
		fields = fmt.Sprintf("[%s] ", strings.Join(keys, ", "))
	}

	level := f.parseLevel(entry.Level)

	return []byte(fmt.Sprintf("[%s] %s%s %s\n", level, fields, entry.Data["source"], entry.Message)), nil
}