func New(key, value []byte) Pair {
	slice := makenz(8 + len(value) + len(key))
	binary.LittleEndian.PutUint32(slice, uint32(len(value)))
	binary.LittleEndian.PutUint32(slice[4:], uint32(len(key)))
	copy(slice[8:], value)
	copy(slice[8+len(value):], key)
	return Pair{unsafe.Pointer(&slice[0])}
}
New returns a Pair
package pair
import (
	"encoding/binary"
	"reflect"
	"unsafe"
)
const maxInt = int(^uint(0) >> 1)
type Pair struct {
	ptr unsafe.Pointer
}