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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 check_id_idx_exclusivity(id, idx):
 """ Makes sure user didn't provide both ids and idx values to subset by. Input: - id (list or None):
 if not None, a list of string id names - idx (list or None):
 if not None, a list of integer id indexes Output: - a tuple: first element is subset type, second is subset content """

    if (id is not None and idx is not None):
        msg = ("'id' and 'idx' fields can't both not be None," +
               " please specify subset in only one of these fields")
        logger.error(msg)
        raise Exception("parse_gctx.check_id_idx_exclusivity: " + msg)
    elif id is not None:
        return ("id", id)
    elif idx is not None:
        return ("idx", idx)
    else:
        return (None, [])