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: message.go
    path of file: ./repos/im_service
    
    the code of the file until where you have to start completion: /**
 * Copyright (c) 2014-2015, GoBelieve     
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Pu
    
func (message *IMMessage) ToDataV1() []byte {
	buffer := new(bytes.Buffer)
	binary.Write(buffer, binary.BigEndian, message.sender)
	binary.Write(buffer, binary.BigEndian, message.receiver)
	binary.Write(buffer, binary.BigEndian, message.timestamp)
	binary.Write(buffer, binary.BigEndian, message.msgid)
	buffer.Write([]byte(message.content))
	buf := buffer.Bytes()
	return buf
}