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: volumes.go
    path of file: ./repos/dry/appui
    
    the code of the file until where you have to start completion: package appui

import (
	"context"
	"errors"
	"fmt"
	"sort"
	"strconv"
	"strings"
	"sync"

	"github.com/docker/docker/api/types/
    
func (s *VolumesWidget) updateTableHeader() {
	sortMode := s.sortBy

	for _, c := range s.header.Columns {
		colTitle := c.Text
		var header SortableColumnHeader
		if strings.Contains(colTitle, DownArrow) {
			colTitle = colTitle[DownArrowLength:]
		}
		for _, h := range volumesTableHeaders {
			if colTitle == h.Title {
				header = h
				break
			}
		}
		if header.Mode == sortMode {
			c.Text = DownArrow + colTitle
		} else {
			c.Text = colTitle
		}

	}
}