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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 select_bed(bed):
 """ Return non-overlapping set of ranges, choosing high scoring blocks over low scoring alignments when there are conflicts. """

    ranges = [Range(x.seqid, x.start, x.end, float(x.score), i) for i, x in enumerate(bed)]
    selected, score = range_chain(ranges)
    selected = [bed[x.id] for x in selected]

    return selected