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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 start_log(level=logging.DEBUG, filename=None):
 """start the logger for the run Parameters level : int, optional logging.DEBUG, logging.INFO etc. for the log level (between 0-50). filename : str, optional name of the filename to save the log to or None (default) to use deblur.log.TIMESTAMP """

    if filename is None:
        tstr = time.ctime()
        tstr = tstr.replace(' ', '.')
        tstr = tstr.replace(':', '.')
        filename = 'deblur.log.%s' % tstr
    logging.basicConfig(filename=filename, level=level,
                        format='%(levelname)s(%(thread)d)'
                        '%(asctime)s:%(message)s')
    logger = logging.getLogger(__name__)
    logger.info('*************************')
    logger.info('deblurring started')