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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 unique(seq, preserve_order=True):
 """ Take a sequence and make it unique. Not preserving order is faster, but that won't matter so much for most uses. copied from: http://www.peterbe.com/plog/uniqifiers-benchmark/uniqifiers_benchmark.py """

    if preserve_order:
        # f8 by Dave Kirby
        # Order preserving
        seen = set()
        seen_add = seen.add  # lookup method only once
        return [x for x in seq if x not in seen and not seen_add(x)]
    # f9
    # Not order preserving
    return list({}.fromkeys(seq).keys())