code: private String formatLevel(Event.Level level) {
          if (level == null) {
              return null;
          }
  
          switch (level) {
              case DEBUG:
                  return "debug";
              case FATAL:
                  return "fatal";
              case WARNING:
                  return "warning";
              case INFO:
                  return "info";
              case ERROR:
                  return "error";
              default:
                  logger.error("The level '{}' isn't supported, this should NEVER happen, contact Sentry developers",
                      level.name());
                  return null;
          }
      }
docs: Formats a log level into one of the accepted string representation of a log level.
  
  @param level log level to format.
  @return log level as a String.