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: presence.go
    path of file: ./repos/whatsmeow/types
    
    the code of the file until where you have to start completion: // Copyright (c) 2021 Tulir Asokan
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

package types

import (
	"fmt"
)

type Presence string

cons
    
func (rt ReceiptType) GoString() string {
	switch rt {
	case ReceiptTypeRead:
		return "types.ReceiptTypeRead"
	case ReceiptTypeReadSelf:
		return "types.ReceiptTypeReadSelf"
	case ReceiptTypeDelivered:
		return "types.ReceiptTypeDelivered"
	case ReceiptTypePlayed:
		return "types.ReceiptTypePlayed"
	default:
		return fmt.Sprintf("types.ReceiptType(%#v)", string(rt))
	}
}