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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 _other_pipeline_samples(summary_file, cur_samples):
 """Retrieve samples produced previously by another pipeline in the summary output. """

    cur_descriptions = set([s[0]["description"] for s in cur_samples])
    out = []
    if utils.file_exists(summary_file):
        with open(summary_file) as in_handle:
            for s in yaml.safe_load(in_handle).get("samples", []):
                if s["description"] not in cur_descriptions:
                    out.append(s)
    return out