code: def _get_block_transaction_data(db: BaseDB, transaction_root: Hash32) -> Iterable[Hash32]:
          
          transaction_db = HexaryTrie(db, root_hash=transaction_root)
          for transaction_idx in itertools.count():
              transaction_key = rlp.encode(transaction_idx)
              if transaction_key in transaction_db:
                  yield transaction_db[transaction_key]
              else:
                  break
docs: Returns iterable of the encoded transactions for the given block header