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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 get_parallel_regions(batch):
 """CWL target to retrieve a list of callable regions for parallelization. """

    samples = [utils.to_single_data(d) for d in batch]
    regions = _get_parallel_regions(samples[0])
    return [{"region": "%s:%s-%s" % (c, s, e)} for c, s, e in regions]