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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_s3_multipart_chunk_size(filesize):
 """Returns the chunk size of the S3 multipart object, given a file's size."""

    if filesize <= AWS_MAX_MULTIPART_COUNT * AWS_MIN_CHUNK_SIZE:
        return AWS_MIN_CHUNK_SIZE
    else:
        div = filesize // AWS_MAX_MULTIPART_COUNT
        if div * AWS_MAX_MULTIPART_COUNT < filesize:
            div += 1
        return ((div + MiB - 1) // MiB) * MiB