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: ssh.go
    path of file: ./repos/devspace/vendor/github.com/gliderlabs/ssh
    
    the code of the file until where you have to start completion: package ssh

import (
	"crypto/subtle"
	"net"

	gossh "golang.org/x/crypto/ssh"
)

type Signal string

// POSIX signals as listed in RFC 4254 Sectio
    
func KeysEqual(ak, bk PublicKey) bool {

	//avoid panic if one of the keys is nil, return false instead
	if ak == nil || bk == nil {
		return false
	}

	a := ak.Marshal()
	b := bk.Marshal()
	return (len(a) == len(b) && subtle.ConstantTimeCompare(a, b) == 1)
}