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: packet.go
    path of file: ./repos/gitkube/vendor/golang.org/x/crypto/openpgp/packet
    
    the code of the file until where you have to start completion: // Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENS
    
func writeMPI(w io.Writer, bitLength uint16, mpiBytes []byte) (err error) {
	// Note that we can produce leading zeroes, in violation of RFC 4880 3.2.
	// Implementations seem to be tolerant of them, and stripping them would
	// make it complex to guarantee matching re-serialization.
	_, err = w.Write([]byte{byte(bitLength >> 8), byte(bitLength)})
	if err == nil {
		_, err = w.Write(mpiBytes)
	}
	return
}