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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 batch_delete_s3_objects( keys, aws_bucket_name, chunk_size=100, s3_client=None ):
 """ Utility method that batch deletes objects in given bucket. """

    if s3_client is None:
        s3_client, s3_resource = get_s3_client()

    key_chunks = []
    for i in range(0, len(keys), chunk_size):
        chunk = []
        for key in (list(keys)[i:i+100]):
            chunk.append({'Key': key})
        key_chunks.append(chunk)
    for chunk in key_chunks:
        s3_client.delete_objects(
            Bucket=aws_bucket_name,
            Delete={'Objects': chunk}
        )