def _add_system(query, data):
    """Add data from successful system MIB query to original data provided.

    Args:
        query: MIB query object
        data: Three keyed dict of data

    Returns:
        data: Aggregated data

    """
    # Process query
    result = query.system()

    # Add tag
    for primary in result.keys():
        for secondary in result[primary].keys():
            for tertiary, value in result[primary][secondary].items():
                data[primary][secondary][tertiary] = value

    # Return
    return data