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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_batch_count(instance, **kwargs):
 """Sample post-save handler to update the sample's batch count. Batches are unpublished by default (to prevent publishing empty batches). If the `AUTO_PUBLISH_BATCH` setting is true, the batch will be published automatically when at least one published sample is in the batch. """

    batch = instance.batch
    count = batch.samples.filter(published=True).count()

    if count != batch.count:
        batch.count = count
        if AUTO_PUBLISH_BATCH:
            batch.published = bool(count)
        batch.save()