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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 delete_group_cached(group_id, broker=None):
 """ Delete a group from the cache backend """

    if not broker:
        broker = get_broker()
    group_key = '{}:{}:keys'.format(broker.list_key, group_id)
    group_list = broker.cache.get(group_key)
    broker.cache.delete_many(group_list)
    broker.cache.delete(group_key)