def __call__(self, event):
        """
        Format an event and bridge it to Python logging.
        """
        level = event.get("log_level", LogLevel.info)
        failure = event.get('log_failure')
        if failure is None:
            excInfo = None
        else:
            excInfo = (
                failure.type, failure.value, failure.getTracebackObject())
        stdlibLevel = toStdlibLogLevelMapping.get(level, stdlibLogging.INFO)
        self.logger.log(
            stdlibLevel, StringifiableFromEvent(event), exc_info=excInfo)

        Format an event and bridge it to Python logging.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/logger/_stdlib.py