old_contents: import csv
  import tempfile
  import os
  
  
  class LastTransactionsParser:
  
    LAST_TRANSACTIONS_FILENAME = os.path.join(tempfile.gettempdir(), 'raapija_transactions_last.csv')
  
    @staticmethod
    def read():
      try:
        with open(LastTransactionsParser.LAST_TRANSACTIONS_FILENAME, 'r') as csvfile:
          reader = csv.DictReader(csvfile)
          return [transaction for transaction in reader]
      except FileNotFoundError:
        return None
  
    @staticmethod
    def write(transactions):
      with open(LastTransactionsParser.LAST_TRANSACTIONS_FILENAME, 'w') as csvfile:
        csv_fieldnames = transactions[0].keys()
        writer = csv.DictWriter(csvfile, csv_fieldnames)
        writer.writeheader()
        for transaction in transactions:
          writer.writerow(transaction)
  
new_contents: import csv
  import tempfile
  import os
  
  
  class LastTransactionsParser:
  
    LAST_TRANSACTIONS_FILENAME = os.path.join(tempfile.gettempdir(), 'raapija_transactions_last.csv')
  
    @staticmethod
    def read():
      try:
        with open(LastTransactionsParser.LAST_TRANSACTIONS_FILENAME, 'r', encoding='utf-8') as csvfile:
          reader = csv.DictReader(csvfile)
          return [transaction for transaction in reader]
      except FileNotFoundError:
        return None
  
    @staticmethod
    def write(transactions):
      with open(LastTransactionsParser.LAST_TRANSACTIONS_FILENAME, 'w', encoding='utf-8') as csvfile:
        csv_fieldnames = transactions[0].keys()
        writer = csv.DictWriter(csvfile, csv_fieldnames)
        writer.writeheader()
        for transaction in transactions:
          writer.writerow(transaction)
  
subject: use utf-8 encoding for last transactions file