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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 set_verbosity_level(verbosity_level=3, logger=None):
 """ Defines logging verbosity level. Available verbosity levels:: 0: Critical. 1: Error. 2: Warning. 3: Info. 4: Debug. :param verbosity_level: Verbosity level. :type verbosity_level: int :param logger: Logger to set the verbosity level to. :type logger: Logger :return: Definition success. :rtype: bool """


    logger = LOGGER if logger is None else logger
    if verbosity_level == 0:
        logger.setLevel(logging.CRITICAL)
        logging.disable(logging.ERROR)
    elif verbosity_level == 1:
        logger.setLevel(logging.ERROR)
        logging.disable(logging.WARNING)
    elif verbosity_level == 2:
        logger.setLevel(logging.WARNING)
        logging.disable(logging.INFO)
    elif verbosity_level == 3:
        logger.setLevel(logging.INFO)
        logging.disable(logging.DEBUG)
    elif verbosity_level == 4:
        logger.setLevel(logging.DEBUG)
        logging.disable(logging.NOTSET)
    return True