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: logrus.go
    path of file: ./repos/docker-ce/components/engine/vendor/github.com/sirupsen/logrus
    
    the code of the file until where you have to start completion: package logrus

import (
	"fmt"
	"log"
	"strings"
)

// Fields type, used to pass to `WithFields`.
type Fields map[string]interface{}

// Level type
type Level uint32

// Convert the Level to a string. E.g. PanicLevel becomes "panic".
func (level Level) String() string {
	if b, err := level.MarshalText(); err == nil {
		return string(b)
	} else {
		return "unknown"
	}
}

// ParseLevel takes a string
    
func (level Level) MarshalText() ([]byte, error) {
	switch level {
	case TraceLevel:
		return []byte("trace"), nil
	case DebugLevel:
		return []byte("debug"), nil
	case InfoLevel:
		return []byte("info"), nil
	case WarnLevel:
		return []byte("warning"), nil
	case ErrorLevel:
		return []byte("error"), nil
	case FatalLevel:
		return []byte("fatal"), nil
	case PanicLevel:
		return []byte("panic"), nil
	}

	return nil, fmt.Errorf("not a valid logrus level %d", level)
}