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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 enable_pretty_logging(logger='calmjs', level=logging.DEBUG, stream=None):
 """ Shorthand to enable pretty logging """


    def cleanup():
        logger.removeHandler(handler)
        logger.level = old_level

    if not isinstance(logger, logging.Logger):
        logger = logging.getLogger(logger)

    old_level = logger.level
    handler = logging.StreamHandler(stream)
    handler.setFormatter(logging.Formatter(
        u'%(asctime)s %(levelname)s %(name)s %(message)s'))
    logger.addHandler(handler)
    logger.setLevel(level)
    return cleanup