func ReadSubscribe(r io.Reader, reserved byte, length int) (Subscribe, error) {
	return Subscribe{}, fmt.Errorf("not implemented")
}
/*
ReadSubscribe reads a subscribe message from a reader.
package mqtt
import (
	"bytes"
	"encoding/binary"
	"fmt"
	"io"
)
type Topic struct {
	Topic string
	QOS   byte
}
type Subscribe struct {
	Topics []Topic
}
type subscribeHeader struct {
	packetID uint16
}