True if the secret for `secrethash` is registered at `block_identifier`.

        Throws NoStateForBlockIdentifier if the given block_identifier
        is older than the pruning limit

def is_secret_registered(
            self,
            secrethash: SecretHash,
            block_identifier: BlockSpecification,
    ) -> bool:
        """True if the secret for `secrethash` is registered at `block_identifier`.

        Throws NoStateForBlockIdentifier if the given block_identifier
        is older than the pruning limit
        """
        if not self.client.can_query_state_for_block(block_identifier):
            raise NoStateForBlockIdentifier()

        block = self.get_secret_registration_block_by_secrethash(
            secrethash=secrethash,
            block_identifier=block_identifier,
        )
        return block is not None