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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 pif_to_mdf_record(pif_obj, dataset_hit, mdf_acl):
 """Convert a PIF into partial MDF record"""

    res = {}
    res["mdf"] = _to_meta_data(pif_obj, dataset_hit, mdf_acl)
    res[res["mdf"]["source_name"]] = _to_user_defined(pif_obj)
    return dumps(res)