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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 _sorter(generated):
 """Return a list of paths sorted by dirname & basename."""

    pairs = [(os.path.dirname(f), os.path.basename(f))
             for f in set(list(generated))]

    pairs.sort()

    return [os.path.join(pair[0], pair[1]) for pair in pairs]