def _errorLoggerForObserver(self, observer):
        """
        Create an error-logger based on this logger, which does not contain the
        given bad observer.

        @param observer: The observer which previously had an error.
        @type observer: L{ILogObserver}

        @return: L{None}
        """
        errorPublisher = LogPublisher(*[
            obs for obs in self._observers
            if obs is not observer
        ])
        return Logger(observer=errorPublisher)

        Create an error-logger based on this logger, which does not contain the
        given bad observer.

        @param observer: The observer which previously had an error.
        @type observer: L{ILogObserver}

        @return: L{None}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/logger/_observer.py