code: func CompareKeys(k1, k2 []byte) int {
  	ko1 := KeyOrder(k1)
  	ko2 := KeyOrder(k2)
  	if ko1 < ko2 {
  		return -1
  	}
  	if ko1 > ko2 {
  		return 1
  	}
  	return bytes.Compare(k1, k2)
  }
docs: // Sorts the keys as if they were compared lexicographically with their KeyOrder prepended