'API endpoint to get details about the status of a transaction or a block.
Return:
A ``dict`` in the format ``{\'status\': <status>}``, where
``<status>`` is one of "valid", "invalid", "undecided", "backlog".'

def get(self):

    parser = reqparse.RequestParser()
    parser.add_argument('transaction_id', type=str)
    parser.add_argument('block_id', type=str)
    args = parser.parse_args(strict=True)
    tx_id = args['transaction_id']
    block_id = args['block_id']
    if (bool(tx_id) == bool(block_id)):
        return make_error(400, 'Provide    exactly    one    query    parameter.    Choices    are:    block_id,    transaction_id')
    pool = current_app.config['bigchain_pool']
    status = None
    with pool() as bigchain:
        if tx_id:
            status = bigchain.get_status(tx_id)
        elif block_id:
            (_, status) = bigchain.get_block(block_id=block_id, include_status=True)
    if (not status):
        return make_error(404)
    return {'status': status}
