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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 to_rec(samples, default_keys=None):
 """Convert inputs into CWL records, useful for single item parallelization. """

    recs = samples_to_records([normalize_missing(utils.to_single_data(x)) for x in samples], default_keys)
    return [[x] for x in recs]