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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 searchone(filename, scan, paramfile, logfile, bdfdir):
 """ Searches one scan of filename filename is name of local sdm ('filename.GN' expected locally). scan is scan number to search. if none provided, script prints all. assumes filename is an sdm. """


    filename = os.path.abspath(filename)
    scans = ps.read_scans(filename, bdfdir=bdfdir)

    if scan != 0:
        d = rt.set_pipeline(filename, scan, paramfile=paramfile,
                            fileroot=os.path.basename(filename), logfile=logfile)
        rt.pipeline(d, range(d['nsegments']))

        # clean up and merge files
        pc.merge_segments(filename, scan)
        pc.merge_scans(os.path.dirname(filename), os.path.basename(filename), scans.keys())
    else:
        logger.info('Scans, Target names:')
        logger.info('%s' % str([(ss, scans[ss]['source']) for ss in scans]))
        logger.info('Example pipeline:')
        state = rt.set_pipeline(filename, scans.popitem()[0], paramfile=paramfile,
                                fileroot=os.path.basename(filename), logfile=logfile)