code: def setOverrideLogLevel(lvl):
      
      if lvl is None:
          return
      logging.info('Overriding log level globally to %s', lvl)
      lvl = getLevelName(lvl)
      global _overrideLogLevel # pylint: disable=global-statement
      _overrideLogLevel = lvl
      logging.getLogger('').setLevel(lvl)
      for loggerName in logging.Logger.manager.loggerDict:
          logger = logging.Logger.manager.loggerDict[loggerName]
          if isinstance(logger, logging.PlaceHolder):
              continue
          logger.setLevel(logging.NOTSET)
docs: Override all logger filter levels to include lvl and above.
  
  
      - Set root logger level
      - iterates all existing loggers and sets their log level to ``NOTSET``.
  
      Args:
          lvl (string): Log level name.