code: func NewEDStore(encryptionCipher string, encryptionKey []byte, idx uint64) (*EDStore, error) {
  	code, keyHash, err := createMasterKeyHash(encryptionCipher, encryptionKey)
  	if err != nil {
  		return nil, err
  	}
  	s, err := newEDStore(code, keyHash, idx)
  	if err != nil {
  		return nil, err
  	}
  	// On success, erase the key
  	for i := 0; i < len(encryptionKey); i++ {
  		encryptionKey[i] = 'x'
  	}
  	return s, nil
  }
docs: // NewEDStore returns an instance of EDStore that adds Encrypt/Decrypt
  // capabilities.