Restore the database from a backup in the backups/ directory.
    If block_number is None, then use the latest backup.

    NOT THREAD SAFE

    Return True on success
    Raise an exception on error

def blockstack_backup_restore(working_dir, block_number):
    """
    Restore the database from a backup in the backups/ directory.
    If block_number is None, then use the latest backup.

    NOT THREAD SAFE

    Return True on success
    Raise an exception on error
    """
    db = BlockstackDB.get_readwrite_instance(working_dir, restore=True, restore_block_height=block_number)
    try:
        db.db_restore(block_number=block_number)
    except Exception as e:
        raise e
    finally:
        db.close()

    return True