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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def setOverrideLogLevel(lvl):
 """ 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. """

    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)