code: def get_utxoset_merkle_root(self):
          utxoset = backend.query.get_unspent_outputs(self.connection)
          hashes = [
              sha3_256(
                  '{}{}'.format(utxo['transaction_id'], utxo['output_index']).encode()
              ).digest() for utxo in utxoset
          ]
          return merkleroot(sorted(hashes))