Retrieve the list of blocks (block ids) containing a
           transaction with transaction id `txid`

        Args:
            txid (str): transaction id of the transaction to query

        Returns:
            Block id list (list(int))

def get_block_containing_tx(self, txid):
        """Retrieve the list of blocks (block ids) containing a
           transaction with transaction id `txid`

        Args:
            txid (str): transaction id of the transaction to query

        Returns:
            Block id list (list(int))
        """
        blocks = list(backend.query.get_block_with_transaction(self.connection, txid))
        if len(blocks) > 1:
            logger.critical('Transaction id %s exists in multiple blocks', txid)

        return [block['height'] for block in blocks]