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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 _task_batcher(tasks, batch_size=None):
 """Batches large task lists into groups of 100 so that they can all be inserted. """

    from itertools import izip_longest

    if not batch_size:
        batch_size = DEFAULT_TASK_BATCH_SIZE

    # Ensure the batch size is under the task api limit.
    batch_size = min(batch_size, 100)

    args = [iter(tasks)] * batch_size
    return ([task for task in group if task] for group in izip_longest(*args))