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: ansi.go
    path of file: ./repos/sealer/vendor/github.com/Azure/go-ansiterm/winterm
    
    the code of the file until where you have to start completion: // +build windows

package winterm

import (
	"fmt"
	"os"
	"strconv"
	"strings"
	"syscall"

	"github.com/Azure/go-ansiterm"
	windows "golang.org/x/sys/windows"
)

// Windows keyboard constants
// See https://msdn.microsoft.com/en-us/library/windows/desktop/dd375731(v=vs.85).aspx.
const (
	VK_PRIOR    = 0x21 // PAGE UP key
	VK_NEXT     = 0x22 // PAGE DOWN key
	VK_END      = 0x23 // END key
	VK_HOME     = 0x24 // HOME key

    
func isAnsiCommandChar(b byte) bool {
	switch {
	case ansiterm.ANSI_COMMAND_FIRST <= b && b <= ansiterm.ANSI_COMMAND_LAST && b != ansiterm.ANSI_ESCAPE_SECONDARY:
		return true
	case b == ansiterm.ANSI_CMD_G1 || b == ansiterm.ANSI_CMD_OSC || b == ansiterm.ANSI_CMD_DECPAM || b == ansiterm.ANSI_CMD_DECPNM:
		// non-CSI escape sequence terminator
		return true
	case b == ansiterm.ANSI_CMD_STR_TERM || b == ansiterm.ANSI_BEL:
		// String escape sequence terminator
		return true
	}
	return false
}