code: def balance_sheet(self, end=datetime.max,
                        format=ReportFormat.printout, output_path=None):
          
  
          rpt = BalanceSheet(self, end, output_path)
          return rpt.render(format)
docs: Generate a transaction list report.
  
          :param end: The end date to generate the report for.
          :param format: The format of the report.
          :param output_path: The path to the file the report is written to.
            If None, then the report is not written to a file.
  
          :returns: The generated report.