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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 dataflag(d, data_read):
 """ Flagging data in single process """


    for flag in d['flaglist']:
        mode, sig, conv = flag
#        resultlist = []
#        with closing(mp.Pool(4, initializer=initreadonly, initargs=(data_read_mem,))) as flagpool:
        for ss in d['spw']:
            chans = n.arange(d['spw_chanr_select'][ss][0], d['spw_chanr_select'][ss][1])
            for pol in range(d['npol']):
                status = rtlib.dataflag(data_read, chans, pol, d, sig, mode, conv)
                logger.info(status)

    # hack to get rid of bad spw/pol combos whacked by rfi
    if 'badspwpol' in d:
        logger.info('Comparing overall power between spw/pol. Removing those with %d times typical value' % d['badspwpol'])
        spwpol = {}
        for spw in d['spw']:
            chans = n.arange(d['spw_chanr_select'][spw][0], d['spw_chanr_select'][spw][1])
            for pol in range(d['npol']):
                spwpol[(spw, pol)] = n.abs(data_read[:,:,chans,pol]).std()
        
        meanstd = n.mean(spwpol.values())
        for (spw,pol) in spwpol:
            if spwpol[(spw, pol)] > d['badspwpol']*meanstd:
                logger.info('Flagging all of (spw %d, pol %d) for excess noise.' % (spw, pol))
                chans = n.arange(d['spw_chanr_select'][spw][0], d['spw_chanr_select'][spw][1])
                data_read[:,:,chans,pol] = 0j