code: def update_utxoset(self, transaction):
          
          spent_outputs = [
              spent_output for spent_output in transaction.spent_outputs
          ]
          if spent_outputs:
              self.delete_unspent_outputs(*spent_outputs)
          self.store_unspent_outputs(
              *[utxo._asdict() for utxo in transaction.unspent_outputs]
          )
docs: Update the UTXO set given ``transaction``. That is, remove
          the outputs that the given ``transaction`` spends, and add the
          outputs that the given ``transaction`` creates.
  
          Args:
              transaction (:obj:`~bigchaindb.models.Transaction`): A new
                  transaction incoming into the system for which the UTXO
                  set needs to be updated.