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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 update_compaction(model):
 """Updates the compaction options for the given model if necessary. :param model: The model to update. :return: `True`, if the compaction options were modified in Cassandra, `False` otherwise. :rtype: bool """

    logger.debug("Checking %s for compaction differences", model)
    table = get_table_settings(model)

    existing_options = table.options.copy()

    existing_compaction_strategy = existing_options['compaction_strategy_class']

    existing_options = json.loads(existing_options['compaction_strategy_options'])

    desired_options = get_compaction_options(model)

    desired_compact_strategy = desired_options.get('class', SizeTieredCompactionStrategy)

    desired_options.pop('class', None)

    do_update = False

    if desired_compact_strategy not in existing_compaction_strategy:
        do_update = True

    for k, v in desired_options.items():
        val = existing_options.pop(k, None)
        if val != v:
            do_update = True

    # check compaction_strategy_options
    if do_update:
        options = get_compaction_options(model)
        # jsonify
        options = json.dumps(options).replace('"', "'")
        cf_name = model.column_family_name()
        query = "ALTER TABLE {} with compaction = {}".format(cf_name, options)
        logger.debug(query)
        execute(query)
        return True

    return False