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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_single(samples, default_keys=None):
 """Convert output into a list of single CWL records. """

    out = []
    for data in samples:
        recs = samples_to_records([normalize_missing(utils.to_single_data(data))], default_keys)
        assert len(recs) == 1
        out.append(recs[0])
    return out