API endpoint to get the related blocks for a transaction.

        Return:
            A ``list`` of ``block_id``s that contain the given transaction. The
            list may be filtered when provided a status query parameter:
            "valid", "invalid", "undecided".

def get(self):
        """API endpoint to get the related blocks for a transaction.

        Return:
            A ``list`` of ``block_id``s that contain the given transaction. The
            list may be filtered when provided a status query parameter:
            "valid", "invalid", "undecided".
        """
        parser = reqparse.RequestParser()
        parser.add_argument('transaction_id', type=str, required=True)

        args = parser.parse_args(strict=True)
        tx_id = args['transaction_id']

        pool = current_app.config['bigchain_pool']

        with pool() as bigchain:
            blocks = bigchain.get_block_containing_tx(tx_id)

        return blocks