How to use the ssh-audit.SSH2.Kex.parse function in ssh-audit

err_pair = ('SMSG_PUBLIC_KEY', SSH.Protocol.SMSG_PUBLIC_KEY)
			elif sshv == 2 and packet_type != SSH.Protocol.MSG_KEXINIT:
				err_pair = ('MSG_KEXINIT', SSH.Protocol.MSG_KEXINIT)
			if err_pair is not None:
				fmt = '[exception] did not receive {0} ({1}), ' + \
				      'instead received unknown message ({2})'
				err = fmt.format(err_pair[0], err_pair[1], packet_type)
	if err:
		output(banner, header)
		out.fail(err)
		sys.exit(1)
	if sshv == 1:
		pkm = SSH1.PublicKeyMessage.parse(payload)
		output(banner, header, pkm=pkm)
	elif sshv == 2:
		kex = SSH2.Kex.parse(payload)
		output(banner, header, kex=kex)