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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 get_max_size(pool, num_option, item_length):
 """ Calculate the max number of item that an option can stored in the pool at give time. This is to limit the pool size to POOL_SIZE Args: option_index (int):
 the index of the option to calculate the size for pool (dict):
 answer pool num_option (int):
 total number of options available for the question item_length (int):
 the length of the item Returns: int: the max number of items that `option_index` can have """

    max_items = POOL_SIZE / item_length
    # existing items plus the reserved for min size. If there is an option has 1 item, POOL_OPTION_MIN_SIZE - 1 space
    # is reserved.
    existing = POOL_OPTION_MIN_SIZE * num_option + sum([max(0, len(pool.get(i, {})) - 5) for i in xrange(num_option)])
    return int(max_items - existing)