func (s *Stamp) Timestamp() []byte {
	return s.timestamp
}
Timestamp returns the timestamp of the stamp
package postage
import (
	"bytes"
	"errors"
	"fmt"
	"github.com/ethsana/sana/pkg/crypto"
	"github.com/ethsana/sana/pkg/storage"
	"github.com/ethsana/sana/pkg/swarm"
)
const (
	StampSize   = 113
	IndexSize   = 8
	BucketDepth = 16
)
var (
	ErrOwnerMismatch = errors.New("owner mismatch")
	ErrInvalidIndex = errors.New("invalid index")
	ErrStampInvalid = errors.New("invalid stamp")
	ErrBucketMismatch = errors.New("bucket mismatch")
)
var _ swarm.Stamp = (*Stamp)(nil)
type Stamp struct {
	batchID   []byte  
	index     []byte  
	timestamp []byte  
	sig       []byte  
}
func NewStamp(batchID, index, timestamp, sig []byte) *Stamp {
	return &Stamp{batchID, index, timestamp, sig}
}
func (s *Stamp) BatchID() []byte {
	return s.batchID
}
func (s *Stamp) Index() []byte {
	return s.index
}
func (s *Stamp) Sig() []byte {
	return s.sig
}