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: level.go
    path of file: ./repos/kratos/log
    
    the code of the file until where you have to start completion: package log

import "strings"

// Level is a logger level.
type Level int8

// LevelKey is logger level key.
cons
    
func (l Level) String() string {
	switch l {
	case LevelDebug:
		return "DEBUG"
	case LevelInfo:
		return "INFO"
	case LevelWarn:
		return "WARN"
	case LevelError:
		return "ERROR"
	case LevelFatal:
		return "FATAL"
	default:
		return ""
	}
}