def write_event(self, event):

        if not self.header_written:
            self._out.write("<stream>")
            self.header_written = True

        event.write_to(self._out)
Make sure print_examples interpolates message with arguments
dataset/ETHPy150Open splunk/splunk-app-twitter/twitter2/bin/splunklib/modularinput/event_writer.py/EventWriter.write_event--crossover with--dataset/ETHPy150Open duerrp/pyexperiment/tests/test_printers.py/TestPrinterExamples.test_example_messsage_with_args