code: public static PortLogger getLogger(String name, OutputCollector output) {
      Args.checkNotNull(name, "logger name cannot be null");
      Map<OutputCollector, PortLogger> loggers = PortLoggerFactory.loggers.get(name);
      if (loggers == null) {
        loggers = new HashMap<>();
        PortLoggerFactory.loggers.put(name, loggers);
      }
  
      PortLogger logger = loggers.get(output);
      if (logger == null) {
        logger = new PortLogger(LoggerFactory.getLogger(name), output);
        loggers.put(output, logger);
      }
      return logger;
    }
docs: Creates an output port logger with the given name.
  
  @param name The logger name.
  @param output The output to which to log messages.
  @return An output port logger.