code: func ValidateTransactionHashes(hashes ...Hash) Validatable {
  	return func() error {
  		for i := range hashes {
  			if !IsTransactionHash(hashes[i]) {
  				return errors.Wrapf(ErrInvalidTransactionHash, "%s at index %d", hashes[i], i)
  			}
  		}
  		return nil
  	}
  }
docs: // ValidateTransactionHashes validates the given transaction hashes.