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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 default_logging(grab_log=None, # '/tmp/grab.log', network_log=None, # '/tmp/grab.network.log', level=logging.DEBUG, mode='a', propagate_network_logger=False):
 """ Customize logging output to display all log messages except grab network logs. Redirect grab network logs into file. """


    logging.basicConfig(level=level)

    network_logger = logging.getLogger('grab.network')
    network_logger.propagate = propagate_network_logger
    if network_log:
        hdl = logging.FileHandler(network_log, mode)
        network_logger.addHandler(hdl)
        network_logger.setLevel(level)

    grab_logger = logging.getLogger('grab')
    if grab_log:
        hdl = logging.FileHandler(grab_log, mode)
        grab_logger.addHandler(hdl)
        grab_logger.setLevel(level)