'Format an event and bridge it to Python logging.'

def __call__(self, event):

    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)
