code: func (tx Tx) Delete(k [][]byte) error {
  	if len(k) == 1 {
  		return errorsp.WithStacks(tx.Tx.DeleteBucket(k[0]))
  	}
  	return tx.Bucket(k[:len(k)-1], func(b Bucket) error {
  		return errorsp.WithStacks(b.Bucket.Delete(k[len(k)-1]))
  	})
  }
docs: // Delete deletes a key.