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: diskusage.go
    path of file: ./repos/buildkit/cmd/buildctl
    
    the code of the file until where you have to start completion: package main

import (
	"fmt"
	"io"
	"os"
	"strings"
	"text/tabwriter"

	"github.com/moby/buildkit/client"
	bccommon "github.com/moby/buildkit/cmd/buildctl/common"
	"github.com/moby/buildkit/util/bklog"
	"github.com/tonistiigi/units"
	"github.com/urfave/cli"
)

var diskUsageCommand = cli.Command{
	Name:   "du",
	Usage:  "disk usage",
	Action: diskUsage,
	Flags: []cli.Flag{
		cli.StringSliceFlag{
			Name:  "filter, f",
			Usage: "Filter records",
		},
		cli.BoolFlag{
			Name:  "verbose, v",
			Usage: "Verbose output",
		},
		cli.StringFlag{
			Name:  "format",
			Usage: "Format the output using the given Go template, e.g, '{{json .}}'",
		},
	},
}

func diskUsage(clicontext *cli.Context) error {
	c, err := bccommon.ResolveClient(clicontext)
	if err != nil {
		return err
	}

	du, err :
    
func diskUsage(clicontext *cli.Context) error {
	c, err := bccommon.ResolveClient(clicontext)
	if err != nil {
		return err
	}

	du, err := c.DiskUsage(bccommon.CommandContext(clicontext), client.WithFilter(clicontext.StringSlice("filter")))
	if err != nil {
		return err
	}

	if format := clicontext.String("format"); format != "" {
		if clicontext.Bool("verbose") {
			bklog.L.Debug("Ignoring --verbose")
		}
		tmpl, err := bccommon.ParseTemplate(format)
		if err != nil {
			return err
		}
		if err := tmpl.Execute(clicontext.App.Writer, du); err != nil {
			return err
		}
		_, err = fmt.Fprintf(clicontext.App.Writer, "\n")
		return err
	}

	tw := tabwriter.NewWriter(os.Stdout, 1, 8, 1, '\t', 0)

	if clicontext.Bool("verbose") {
		printVerbose(tw, du)
	} else {
		printTable(tw, du)
	}

	if len(clicontext.StringSlice("filter")) == 0 {
		printSummary(tw, du)
	}

	return nil
}