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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 save_file(client, bucket, data_file, items, dry_run=None):
 """Tries to write JSON data to data file in S3."""

    logger.debug('Writing {number_items} items to s3. Bucket: {bucket} Key: {key}'.format(
        number_items=len(items),
        bucket=bucket,
        key=data_file
    ))

    if not dry_run:
        return _put_to_s3(client, bucket, data_file, json.dumps(items))